Originally Posted by Edvin
I could not find any mention of something like "save game editor" but people have already begun to create mods that are able to add new skills or tags and I thought that these people use programs that could help me with my problem.

So in a sense it's a question about modding. hehe

They use a combination of the Divinity Engine 2 (https://docs.larian.game/The_Divinity_Engine_2) and .pak extraction (https://docs.larian.game/Pak_Extractor_Guide).