I hope it’s okay to make another post right after my previous one

It is now possible to create new quests in Divinity 2. Well... almost. I’ve released the first version of a sample quest-authoring workflow together with some reverse-engineering documentation of Divinity 2’s scripting and quest systems:
https://github.com/PmNz8/divinity2-quest-authorThe research is already further along than what is currently available on GitHub. It is possible to work with quest items, spawn and remove them from the world, create multiple possible endings, add quest rewards, and more. I also have a tool for injecting a new quest into an existing save from different points in the story, although it has not yet been proven to work universally. For now new quests require fresh start.
The engine requires quests to be pre-registered in the default save file. The game ships with initial saves that already contain these registrations, which are used when starting Ego Draconis or Flames of Vengeance. The tool injects the new quest into the starting saves and uses the DKS_Patch override priority to avoid touching any game files.