>>54388144Males carry egg moves and can pass them on, like pokémon. And where do you think the people with superhuman abilities came from in Pokémon. Sabrina had a Psychic type ancestor in her tree. Chuck's mama likely had a thing for fighting types, as he's able to spar full title with his crew.
Or maybe we're thinking too small. Maybe since the emergence of humans alongside pokémon, they've been cross-breeding with each other and by tghe time of the games we play human bloodstock has become so utterly cross-pollinated that emergence of elemental affinity is a natural part of the world, the only question is which typing's going to be your huckleberry.