Ingo is one of the two Subway Bosses in the Unova Based games (Black, White, Black 2, and White 2), or one of the Pearl Clan's Wardens in Pokémon Legends: Arceus.
Game canon:
Ingo runs the Battle Subway in Unova in the long sprawling Battle Subway, located in Nimbasa City, with his brother Emmet. He is the older brother of the two and loves Single Battles. Ingo's main partner is a Chandelure.
He appears in Pokemon Masters EX, and his partner is Excadrill.
At an unspecified point, Ingo falls through a crack in space and time, falling in the ancient time period of Hisui (Sinnoh). He had lost his memories and his Chandelure, only with few recollections of his past life and what Unova may have been. He still speaks in subway-lingo, but no one understands him. Ingo, part of the Pearl Clan, became a Warden to watch over Sneasler, but once Sneasler is tasked to the player, rei-legends or akari-legends, he becomes the manager of the Jubilife Village Training Grounds. He can be fought here.
GOTCHA
He makes a cameo appearance in this.