**MADE THE FOLLOWING STEP ON MY JAILBROKEN PS4**
1; i have set my autosave slot on slot 10 as saying in the post, then i copied my gamesave to my usb and copied it to my pc (so i have a backup and now i can transfer the modded save without overwriting my own save
2; transfered the modded save on my usb drive then i went in apollo save tools to resign the save to my account.
3; after resign i copied it to my savegame storage through the settings menu
4; still using apollo save tool i went in my hdd saves after transfering it from the usb, then went on the save game, then selected [Export decrypted save files (should extract a file named GAMESAVE10 in "/data/apollo/{userid}/CUSA00103_GAMESAVE10/GAMESAVE10"]
5; then replaced the modded save with my own save through settings
6; again in apollo, i went on my save game, this time i clicked [Import decrypted save files (selected the extracted GAMESAVE10)] then clicked [Apply Changes & Resign]
YES transfering the save on your ps5 after resigning works, it's what i did after these steps and the trophy unlocked successfully