That changes things a bit. When you said 2 switches I assumed you meant two separate switches, not a switch like that.
There are a few posts in the community that have tackled similar use cases like yours, so I’d recommend searching for solutions.
There are microswitches that can be tucked away in the box, and/or in the fan’s ceiling box, so you can preserve the wall switch. What I would not recommend you do is use smartbulbs in the fan.
Having a neutral there is important, and perhaps each black wire is the hot for the lights and the other is the fan, but you’re going to want an electrician to help you out.
Here are some search results for you to read through that should help you out, and to ask your questions there as well. Lot’s of smart folks in these discussions.
https://community.smartthings.com/search?q=ceiling%20fan%20switch