Update, July 7, 2022:
After downloading latest update/patch 1.003.000 you can officially auto pop the platinum. However it’s not instant platinum unfortunately. What you need to do is the following,
-after re sign the save to yours. Have the PS4 save via USB downloaded to your PS5.
-Start the PS5 version, Click New Game, click down on the D-pad to import your PS4 save.
-The game will restart and some trophies will auto pop.
-Leave the garage with any car. And click down on your d-pad at times trophies will auto pop.
-Now close application, and DELETE ONLY YOUR PS5 SAVE ONLY
-Start the game and repeat. It might take you few tries. It took me 3 attempts to pop the platinum trophy.
Finally we can kinda auto pop all trophies.
Good luck everyone and happy trophy popping lol