This will probably work on other distributions feel free to ask questions if you need help. I'm not an expert on Balatro or installing mods, this is just how I figured out how to setup my system.
I do not know how to mod the GOG version after going back and forth with a troll I will not spend any of my time trying to figure it out, sorry. I do not use GOG and I do not have a sus copy of the game to experiment with and try to figure it out.
I cannot help you mod the game, I don't know how and have very little interest in learning. There's a guide here which might help: https://steamcommunity.com/sharedfiles/filedetails/?id=3400691352