User and target swap items.

Switcheroo switches the user's currently held item with the target's currently held item.
If only one target is holding an item, it will simply be moved to the other.
The ability Sticky Hold prevents items from being stolen.
The following items are always unable to be swapped:

• Griseous Orb from a Giratina
• Any Type Plate held by Arceus
• Any Drive held by Genesect
• Any Mega Stone held by a Pokémon that can use it to Mega-Evolve
• Any mail item such as Grass Mail
• Any e-Reader berry such as Pumkin Berry
• Any Z-Crystal such as Buginium Z
• Any memory item such as Bug Memory held by Silvally
• Rusted Sword if either the user or the target is Zacian
• Rusted Shield if either the user or the target is Zamazenta
• Booster Energy if the target is a Paradox Pokémon (excluding Koraidon and Miraidon).
• Wellspring Mask, Hearthflame Mask or Cornerstone Mask if either the user or the target is Ogerpon

Wild Pokémon can not swap the user's held item.

• In Gen 4 Switcheroo swaps the items permanently but fails if used by a wild Pokémon or an NPC Trainer Pokémon.