Krisi

Hello there! Since you solved your issue, I will go ahead and move this topic to solved topics. If you have anymore issue in the future, feel free to contact us again. Kind regards, Krisi TruckersMP Support //Locked and Moved to Solved

The reason for this is simple, the base game and TruckersMP Launcher use different prefix folders, you need to insert the mods into the folder where the TruckersMP Launcher Proton prefix folder is located. I'll post a more detailed fix, but if I give a clue for you until that, I'm glad I was able to help.