Try cleaning you cache as suggested in this thread: https://steamcommunity.com/app/1086940/discussions/3/4032473436326468727/
It should be located in ~/.local/share/Larian Studios/Baldur's Gate 3.
I have BG3 from GOG and got the Linux binaries from a friend.
I feel like this could be the root of the problem. The icons in the Windows version of the game might be in a different format, so the Linux binary is looking for files which do not exist. Something like that.

