>>29477762That wouldn't really work, would it
Surely in this hypothetical prequel, there would be less than 151 Pokemon discovered/available, there wouldn't be a Dex, many features like the PC System would be nowhere near as advanced (or even there at all). Oak and Agatha are also very independent characters with different goals and personalities, I don't think it's fair to just play them off as gender-swaps of each other - there'd have to be changes in the campaign based on whether you're a boy or a girl, and I couldn't ever see Game Freak doing that.
I'd like to see Oak/Agatha stuff in the future though, and many of the towns of Johto I'd like to see in "past states" (like maybe 50 years ago, before Radio Tower was built, etc). They should really do more Celebi events for fanwank stuff like this.