One of them will evovle from Nebby (I'll make it a 50/50 which one you get) then will carry you to an alternate dimension to get the other one.
That's also where the girl version of the MC will be met
Viewing post in The Legendary Pokemon Breeder comments
A chance to knock up our own AU? Makes me have a crazy idea of our Pokegears being cross dimentonal and her not being a Legendary whore and more like a twin to the brother of a sister we didn't know we had and in the same chapter same sister sees us return and joins our harem. Maybe? I'm just spitballing cause idk how you feel on "selfcest" and "incest" so I will 100% understand if you don't do either