I've been doing some testing on Android. PqSave only requires a small modification to get the AES key from shared_prefs
Unfortunately when Internet is available, the game immediately resets at startup with a message "the backup is used on another device...".
And that's even though I never made...
On the series s/x you can use a external HD but any next gen games must be on your internal ssd, or you can buy a ssd expansion card, but pricey. Any xbone, 360, or og Xbox games can be played from external tho.