Larian Studios Forums Divinity - Original Sin Divinity Original Sin - Mods All resources are duplicated after extracting PAKs

I guess it is because you copied the data dependency on main while also copied it to your mod folder. This means it reads both from your mod folder and the main data folder.
What I guess you need to do (if you want to copy everything) - is to only make it reliant on the mod you created, and not the Main's data. (if you can uncheck that box, idk.)