StarCraft 2 definitely works on Linux, with a relatively simple act of adding it to Steam as a non-Steam title, and then letting the Proton layer do its thing.

And this is coming from a very Linux-hesitant newbie who mostly uses Windows.

I have not tried Fortnite.

https://www.reddit.com/r/linux_gaming/comments/ppgk04/starcr...

Starcraft 2 worked well for years.

Fortnite doesn't work because Sim Tweeney doesn't want it work: both BattleEye and EAC can work on Linux, Epic just chooses not to enable that functionality.

I played starcraft2 13 years ago on Linux, the wizard installer worked just fine.