>>52346290or, it's not live birth either.
pokemon pulls a lot lorewise from medieval misconceptions about how reality works.
the exactly 1 time we ever 100% known egg origins, it's Arceus itself creating it.
And what idea did the medieval world have? Divine Spontaneous Generation. God didn't just make things the first 7 days of the weak, animals are still appearing, often when too much of a thing exists. Flies appear from rotten fruit (or muk from toxic sludge) or when God (arceus) decides to make more.
(Also that some animals turn into other animals, like the goose barnacle becoming the barnacle goose. sound familiar?)
I think Arceus personally creates every single fucking egg. He sees two pokemon getting along, and then decides to make a pokemon as a child for them (or their human partners) to raise. And then the two parents make that protective egg-nest thing the way elm describes.
