Uh, if anyone wants an all purpose, virtual file system creating, mod manager that works for basically any game, once you configure it right:

Limo.

https://github.com/limo-app/limo

Should just be in Discover if you're on SteamOS or Bazzite... or any LinuxOS with Flatpak ... its been on flathub for a while.

Ive been using it on my Steam Deck for a bit over half a year now, have already successfully used it to mod FONV and CP77... all you have to do is set up a profile config that points at the correct directory for CP77, and set up the mod deployer.

You still have to do some manual installations into the core game directory, or some other work around, for things like NVSE, or other mods that override or hijack the core exe or do something else far more 'instrusive', but yeah...

I got tired of waiting for Nexus to actually do this update they've just done here, and ... well MO2 works, but you have to run it through Wine or Proton or Steam Tinker Launch or ... bleh, just too many extra steps, not native...

And Limo works, natively on Linux, just gotta RTFM.