I'm using the OSX version of BG3 (bought on steam).
BG3 says that i have version 4.1.83.2865 and my friend who bought the game as well but he is using windows has a different version than mine, it is: v4.1.83.2651.

My only guess is that the versions differ because of the OS... In any case, we can't join a lobby together, we get an error saying that we have different versions.