Can be used in matchmaking or anything.
You have to NOT be host for it to work.
Works with Overshield or Custom Powerup - Just not with Camo
Use a BubbleShield or a Re-Gen, Simply slowly walk into the O.Shield, holding RB (Right Bumper)[as if to exchange equipment] and the equipment will be swapped for the O.Shield.
Like I say, doesn't work if you are host. Also - It Does indeed work in matchmaking. This is done in Rumble Pit (Social)