It probably is because it doesn't have enough buttons, unfortunately. :/ Back in DI 1.0, it was allowed (at least for Player 2,) but it was super awkward because both the camera controls and the item swap were mapped to the D-pad, so one would equip and unequip items while trying to move the camera. Also, in 2.0 they added super moves, which require another button, which the Wiichuk lacks...