[bityard]

If a game works on Proton (http://protondb.com/), it will almost certainly run on the Steam Deck. And the Steam Deck UI does a pretty good job of highlighting games that run well on the Deck and telling you what the compatibility issues are, if anything.

Assuming the game itself runs fine, usually the main issue is mapping steam deck controls to the in-game keyboard and mouse config. I find the UX for doing this to be pretty confusing and terrible (doubly so when using an external controller), but this is helped some by the fact that you can apply controller mappings submitted by other Steam users.