Ainu folktale of twin sons born from eggs and descended from a divine deity

The Ainu too appear to own a folktale of twin sons birthed from an egg descended from a god, which sounds strangely similar to the tales of the Korean King Suro and other Kaya and Sillan golden egg royal births, see:

“The concubine who bore twin sons in the shape of eggs and whose father was a god” — Guide to Carl Etter Papers and Photographs
on Ainu Folklore and Culture 1931-1932, 1949