So, you’ve connected external storage to your Xbox One, and you want to move a bunch of games at once. (You can move things one at a time, of course, by going to your games & apps collection, focusing on a game, pressing the Menu button on your controller, and selecting Manage game.)
To move or copy multiple games at once:
Connect external storage (devices must be USB 3.0 or faster and 256 GB or larger and formatted for Xbox One).
Press the Xbox button to open the guide, then go to Settings > System > Storage.
Select the storage you want to move or copy from, then select Transfer and make your choices. Select all games or only some, then choose either Copy selected or Move selected.