We have tested and confirmed that the MaxxStick R3 Pro and S3 Pro work with Xbox Series S and X. However, the MaxxStick needs to be in Keyboard mode. In Keyboard Mode, your movement is limited to 8 directions (Up, Down, Left, Right, and the corresponding diagonals). 360-degree movement is not supported.
Now, when you operate the MaxxStick’s thumbstick, your character should move.
Hope this helps.