I have in my living room 2 walls and each wall has 2 lights and on each wall the 2 lights have there corresponding switches.
I would like to find an option so that on one wall I can add a second light switch to also be able to turn on and off the lights on the opposite wall that are also controlled by the other light switch.
I have yet to buy into a platform so I am hoping to get something that is compatible with other platforms like Vera or Hubitat. wifi is also a possibility.
I’m assuming you are in North America because of your use of the term “virtual three-way“ (rather than “virtual 2-way,” which would be the term used in Europe) , but I just wanted to be sure because the device selection does vary.
In any case, there are many ways to do this now. Typically the auxiliary switch will be a battery operated or kinetic energy device, which lets you put it anywhere. Although there are some that are mains powered as well.
Lutron was one of the earliest companies to provide these, and for the last few years they have offered their Caseta line, which is intended for do it yourselfers. They use their own proprietary frequency which is very fast and reliable and operates locally. But they also have their “SmartBridge Pro” device which then allows for all kinds of integrations with other systems. So they work with echo, Google assistant, smartthings, Hubitat, HomeKit, and many more. Excellent devices, these are what I use in my own home. 
If you want to go with Z wave, which again will work with smartthings or vera or Hubitat, then gocontrol makes Mains powered switches which are specifically designed for a virtual three-way, the WD500 and the WT00Z. Those will only work with the voice assistants if you also have a hub.
If you have a smart Device which smartthings can recognize, you can use it to trigger any other device which SmartThings can recognize, so you have a lot of options. However, there may be a slight but noticeable lag, so this is usually more popular for situations like having a single switch which will turn on yard lights on all four sides of the house at once. Not lights in the same room as the switch quite so much, because then the lag is more noticeable.
There are other options as well, but in any case, you should not have any difficulty finding choices. 
If you’re using any device that is wired to the electrical mains, you should consult your local electrical code to make sure that the wiring scheme is approved. Usually, the switch manufacture provides a number of possible wiring diagrams depending on your situation. Zooz switches provide an enormous amount of detail and also now include a really nice warning that says not to simply trust that the wire colors match the colors used in the diagrams.
It seems that, at least in the States, wire colors are more a suggestion than a rule. In other locales, it is a required part of the code. In my locale, one can wire a switch as a virtual 3-way without violating code. Other locales might not allow it.
All that does mean that JDR’s suggestion of battery-powered or kenetic-powered switches may simplify the situation a lot because they don’t have to be wired in.
Whatever you do, I also find it very helpful to take a picture of the existing switch, showing the current connections, that I can refer to in the course of upgrading to automation-friendly switches.
I use a number of z-wave switches (Honeywell, GE, and Zooz) as well as a dimmer switch by Lutron Caseta (because it was in a style that my wife preferred and no one else had a similar model). As JDR points out, to work with SmartThings (and others) you need the SmartBridge. It imposes an additional one-time cost, but it works quite well with ST once connected.
So Leviton Does make a Z-Wave and a Wifi version. I saw on Zigbee website certification for a Leviton Zigbee model but cannot find it anywhere. Since I already have an Amazon Echo Plu which is a basic hub I would prefer to get the Zigbee one. They provide just Like Go Control a dimmer switch with virtual 3-way. This way when I decide to go to a serious HA system I can continue to use it. Leviton sells a lot of data and electrical equipment and is carried by most electrical contractor stores so they would not mis-label the wires. Thanks for the advice. IT helped me find what I am looking for.
The Leviton zigbee devices are intended for hotels and office buildings, the line is not typically sold individually to consumers.
Home Controls usually has them for individual sale, though.
https://www.homecontrols.com/Leviton-Decora-Smart-Lumina-RF-15A-Switch-LVDL15S1BZ
And see the community FAQ for other zigbee options:
You can also accomplish a “virtual 3-way” with any Z-Wave switch by providing power, neutral, and ground to it (it needs to be installed in a regular electrical box). So if you can accommodate that, it will probably be cheapest to get a regular Z-Wave switch given that Lutron or Leviton can be twice as expensive as some of the value brands out there.
Like @JDRoberts, I also use Lutron’s Caseta product line to accomplish this task. Lutron’s Pico remotes make this a truly trivial exercise. You do NOT even need to add a new electrical box, nor expand your current electrical box to use the Pico Remotes. They have a mounting kit that allows them to be surface mounted to any wall, so they look like a standard light switch. The Pico batteries are rated for 10 years as well, and they only cost about $15 (plus the mounting kit for about another $5).
You can even take an existing 'single-gang" wall switch, and add a Pico remote to it by simply changing the wall switch plate from a single gang to a dual gang wall plate. The pico then simply surface mounts alongside your existing switch.
The Pico Remotes can be directly paired to a Caseta Switch or Dimmer, with no need for any home automation hub or controller whatsoever. Like @JDRoberts, I use the Lutron SmartBridge Pro2 to provide integration with Amazon Alexa, Google Home, Apple Homekit, and Hubitat Elevation. It also works with SmartThings, albeit via a cloud to cloud integration, whereas Hubitat uses a local LAN integration for improved speed and reliability.
Except that the Lutron auxiliary switch is about half The cost of most other smart switches.
So specifically when you are budgeting out a project with three-way or four-way set ups, Lutron can be very cost competitive, particularly for a set up which will give you dimming from the auxiliary switch as well.
A bundle of one Lutron Caseta dimmer switch and one pico auxiliary is generally around $50. And if you want a four-way set up, you can add an additional pico for another $15 or so. So then the price is very competitive compared to zwave master switches at each position. 
Amazon carries them:
https://www.amazon.com/Lutron-Wireless-Lighting-P-PKG1P-WH-Assistant/dp/B00JJY1QG0
But many community members buy Lutron devices from energyAvenue.com, A no-frills warehouse operation where Lutron prices are typically 10 to 15% less than other suppliers.
https://www.energyavenue.com/Lutron/P-PKG1W-WH
I’m not saying that’s the right choice for everyone, I’m just saying that while an individual Lutron Caseta switch is quite expensive, their three way bundles are not.
I use Lutron Caseta switches in my own home and we have been very happy with them, but we were looking for devices that would also work with HomeKit.
So as always, different things will work for different people.
My only issue with the Lutron solution is that it requires an internet connection to communicate with the Hubs I have looked at. For example my internet went down yesterday for 4 hours and the Echo Hub was still able to control the zigbee devices but not my other devices like my Door Lock which is August.
Does the Luton solution require me to have internet in order to use automation?
Lutron does not require an Internet connection to work with either wink or hubitat. Or with Apple HomeKit. It will run locally in all three of those cases. So again, different things will work for different households. 
JD Thanks for that. How about for Amazon Echo Hub? If you don’t know I will check. The idea is to start with using what I have as I am torn between all the hub options. But if I start with the most compatible options that use locally enabled hubs when I do make a decision I will not be tossing stuff away which is what I am tired of doing.
I also have an echo show second generation which acts as a zigbee hub for my back up switches.
The echo devices do not connect directly with the Lutron devices, so while there is a good integration, it is cloud-based.
If you want something that will work with echo voice controls when the Internet is out, then it needs to be zigbee. I don’t think the Amazon local voice control works with local Wi-Fi devices yet. But to be honest I’m not 100% sure on that, it’s a pretty new feature.
Unfortunately, there aren’t any of the zigbee devices that can give you a virtual three-way if you are only using echo as the hub.
There are some Wi-Fi switches that work with echo and can do a virtual three-way, I just don’t know if they can do it when Internet is out. ( you set up the three-way through the switch’s own app, not through echo.)
I know Leviton just had a new zigbee dimmer certified on February but it has yet to be made available for sale. I found it on the Zigbee website and when I called Leviton they confirmed it is coming very soon. Not a lot of details but I am hoping it can also do 3-way.
Are you saying Virtual 3-Way has to be managed by the hub or do the devices pair with each other?
First rule of home automation: “the model number matters.“ There are some models where the virtual three-way is handled through the hub. There are other models where The two devices can be paired directly to each other without the hub. So it really just depends on exactly what devices you have.
Also, up until now all Leviton smart switches have used essentially the same wiring methods and do require a physical traveler wire between the master switch and the auxiliary. With some hubs, such as smartthings, you can create a virtual three-way between two Leviton masters on two different circuit branches, but that’s where it depends on the exact models involved.
Here’s their most recent switch, which is Wi-Fi, and you can see the wiring diagrams to the accessory switch do require a physical traveler wire.
https://home.leviton.com/products/decora-smart-wi-fi-600w-universal-ledincandescent-dimmer/
I don’t know if the new Leviton zigbee switch will require a traveler wire or not, I haven’t seen the specs on it.
The issue is that at present, the echo plus cannot set up a switch that is triggered by another switch when no other hub is involved. That may certainly be a feature that Amazon adds in the future, but it’s not there now.
I am making an assumption but I would think it would follow the same logic as the Z-wave unit.
If the Leviton zigbee switch is physically the same as the Leviton Z wave switch, just with a different radio module inside (which is what they have done up until now for most of their models), then it will require a physical traveler wire To use its own accessory switch, so no virtual three-way that way. 
That means you are dependent on the hub, which means you need something more than just an echo plus. At present.