Larian Studios Forums Divinity - Original Sin Divinity Original Sin - Mods Trigger to move Player

There is a topic around the forums that explains it.

It's basically unpacking Main.pak and copying the CharacterCreation folder from Mods/Main/Level and Mods/Main to the respective directories of your mod.

Then rename both your player characters to Player1 and Player 2.

Finally use the code I used up above and set starting level to CharacterCreation.