This effect can only be activated once per turn. This is a Quick Effect that can be activated by choosing 1 of the "●" effects. (Neither of the "●" effects target. Detaching 1 Xyz Material is a cost to activate this effect.)
"You can detach 1 Xyz Material from this card; each player with a handshuffles their entire hand into the Deck, then each player draws the same number of cards they shuffled into the Deck." effect can be activated even if one player does not have any card in their hand. (This effect will only be applied to the player with cards in their hand.) However, this effect cannot be activated if both players have 0 cards in their hand.