Update: Alright, after changing the export settings in Blender everything is now working as intended 
No weird adjusting to the rotation neccesary anymore.
Thanks for your support during this crisis 
10/10 - would walk in again
Update: Alright, after changing the export settings in Blender everything is now working as intended No weird adjusting to the rotation neccesary anymore.
Thanks for your support during this crisis
10/10 - would walk in again