They might give Ash's Incineroar Lash Out instead of Darkest Lariat. Ash's Incineroar doesn't need Darkest Lariat, since Ash doesn't have Incinium Z. While Darkest Lariat is Incineroar Signature move, not every Pokemon Ash owns gets its Signature move and we have seen Darkest Lariat enough under Kukui, while Lash Out needs to be promoted as a move in the anime.