In Co-op mode, Alte's stats and passive do not change.
Alte's Hyper, Self-Destruct, has a different effect in Co-op. When used in a battle, if the player is KO'd during the battle, they will not lose any stars and the opponent will not gain any stars or wins. In addition, the opponent will take damage equal to the player's max HP. If the opponent is KO'd by this damage, the opponent will lose half of their stars.
Alte's passive and Hyper are unchanged in Bounty Hunt mode.
Alte's base stats give her 40 starting stars and a price adjustment of 0% at shops.