Sounds like an interesting and positive proposal, from my POV.
Though, like @Perpete said, it should very much depend on the interest of going through with it and, equally importantly, if it would make sense, in terms of resources to get there (both in developing but also in having players interested in such a move).
Maybe there could be an "intermediate" stage where a 2nd (female) team would be exempt/cheaper for some time (assuming a "new" league), after which it would be like a "normal" 2nd team, in order to promote it in the early stages.