I have tried putting in flash drives and copying over like you're wondering.
It works, the only thing is, if you have multiple accounts with different games, and you move it from its original licensed Xbox to a new one, you will have to sign in to the account linked with the game you want in order to play it, otherwise it will NOT start up, even if it shows in your list.
But if you do not mind constantly switching profiles trying to figure out which game is linked with it, then by all means go for it
I'm not sure if i made sense, LMK