Utilizing specialized software like save swapper tools or hex editors to modify the new save’s Xbox User ID (XUID) so it matches your own account.
Third-party save files are not always compatible with the latest game patches. Many users report that after a Title Update, their “all cars” save becomes corrupted, resetting their entire progress to zero or making the game crash on launch. forza horizon 5 all cars unlocked save game exclusive
If you want, I can: