How to transfer your save data from uplay/ubisoft connect to steam

This is a guide to transfer save data for people who owned on uplay/ubisoft connect that wants to use their save data on steam after buying it later.

The solution

Small guide:
1. First install the game via Steam or put in the Uplay files in this folder:
C:\Program Files (x86)\Steam\steamapps\common\Assassins Creed Origins (You might need to create this folder) and press download/play. Steam will discover the files if necessary.

2. Boot up the game and turn it off again

3.1 Make sure to backup this folder: C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher\savegames\

3.2 Go this location: C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher\savegames\<UPLAYID>\3539 and put the files from this folder into this one:
C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher\savegames\<UPLAYID>\4923
if you need to create a 4923 folder for the game. Steam will automatically create one the first time you launch the game.

4. Boot up the game via Steam again and load your save file. You should unlock all of the previously earned achievements at once and have your save game available. No work arounds required.