For the Leviton, you have multiple choices. It depends in part on exactly the type of bulbs you’re going to control with it. Their universal dimmer is a really nice switch that can handle dimmable fluorescents as well as dimmable LEDs, but it does cost more than some of their other models. There are several Leviton models listed on the official compatibility list.
https://www.smartthings.com/works-with-smartthings/-/filter/brands/Leviton
The user manual for each Leviton master switch will tell you which auxiliary switch to use with it. Or you can contact Leviton support and ask. Leviton calls their auxiliaries “remotes” because they are just acting as a remote control for the master switch.
One thing to note about the Leviton is is that they have an unusual switch design where you only press the bottom half of the rocker whether you are turning on or off. Some people prefer a more conventional rocker like the Homeseer.
Here’s the homeseer thread
