A couple weeks ago I installed Genshin Impact on my Steam Deck and the guide made me run the installer/game.exe through Steam and enable Proton, and it worked flawlessly…can I just do that for everything? Like for instance installing Fortnite Via Epic instead of Heroic (just as an example)?
Epic, EA, Uplay are very well on SD, and you can add them in your Steam library and install games on their platforms. Google non steam launcher, it is very helpful.