I found out you can only keep the characters inventory, but after inserting the save (save.json needs to be renamed into 1.json and moved into saves folder) from 0.8 there are a few things that happen:
1. You keep the characters inventory
2. You keep the stats
3. You keep some quest data
Problems that appear:
- The map isn't saved and thus chest loot is reset
- The doors remain locked
- All character positions in the world are reset including main character's position.
- Some quests are reset like the stove one, although you can still get the fetch quests like normal.