After transferring 16 characters and 20 mules I found some nasty bugs and fix to them.
after 20.11 patch game can start to crash or even didn’t start (I got this).
Fix: redownload game.
game crash while trying to download save.
Fix: delete all save data on ps5
after transfer: character loose artifact slot
Fix: before uploading characters put all dlc artifacts in the bank( pearl etc).
Also guardian perks work but rank will be set to 1.