In Pokémon Let's Go, Pikachu! and Let's Go, Eevee!, the three ghost master trainers are named in reference to the hosts of Game Grumps. Psychic Arin, Psychic Danny and Psychic Ross are named after the hosts Arin Hanson, Danny Avidan and Ross O'Donovan; respectively.
In Bloodstained: Ritual of the Night, entering either code "Egoraptor" or "Grumps" as the file name will unlock the "Hey I'm Grump" or "I'm Not So Grump" accessory; respectively, which are masks of Arin and Danny's Game Grumps faces; respectively.
Members of Game Grumps (Ross, Barry and Brian) on Switch Rally.