With the hdd i did a test on my xbox 360 and when i put a another hdd it put the version of when the console of the hdd so maybe you can use the hdd of xbox 360 and put a modded firmware and after you put the hdd it put modded firmware and before you all say "yes but it stupif you can't" its not...
without pubg popping off, fortnite wouldn't add battle royale, and call of duty wouldn't go even shittier than it did before because of blackout, warzone and dmz