Don't think we going to get any info on this because i don't think SE have work on how anything else look beside eorzea. They can't show something they don't know themself

We know that every race beside elezen are from islands far from eorzea and elezen are the people who was born and grow up in eorzea. But if the lore team did came up with information on other island and how each race grow up and how there area look i love to hear that.