I can't guarantee this will work, but your only option may be save mounter. do note that some saves require a specific version of the game. I only encountered one of my saves that way, and it was trials fusion (the first game I bought on the ps4). it required an update to be recognized otherwise it didn't work. this was moving the save from one account to another on the same system with the same firmware. I know that a different system will work, but I don't know if firmware will pose a problem.