>>52979836A decent portion of the dual-type normal types can be explained by normal being the closest thing to a sound type. Jigglypuff, Mega-Audino, Meloetta, Pyroar, and Drampa all learn Hyper Voice naturally. This is more of a stretch, but Girafarig, Hisuian Zoroark, Heliolisk, Oranguru, Obstagoon, Indeedee, Ursaluna, Arboliva, and Cyclizar can learn it by TM/TR when not many Pokémon of their secondary types can.