This is not the solution which is good. I read that the APP is now out of Beta so I decision to install it before EA force it on me.
I played sims4 in two language English and German without issue. I could change the language just fine without to deinstall and install again in origin. With the APP I need to uninstall the whole game and reinstall that I can play in another default language.
My English folder was always my more modded folder. My german folder was always my vanilla/light modded game. Sometimes I let play children with my sims4 copy and then I switch always to german because they don’t understand English but now, I can’t just switch language anymore because I need to download first 53 GB that they can play. Please make it possible that we can again switch language without the need to reinstall the whole game.