I’m still at a yotal loss as to the purpose.

The button positions never move, only the letters or colours. You don’t look at your hands when you’re playing, so I don’t get why you’d need to swap buttons at all, outside of a game menu.

If you’re used to blue being left or X being bottom or whatever, do that in the menu. Your thumbs can’t see the buttons so it makes no difference. You have bought a controller to do what a menu does for free at the click of a button (a button that means whatever you assign it to mean).