I wouldn't expect to see any geometry difference between the male/female versions of a bike of that age. That idea didn't become common until later.
And even now, is generally only found on more performance oriented bikes.


Even today, most WSD bike frames are simply a little higher for the same overall fore-aft length when compared to the male models. Angles, fork rake etc tends to stay the same.


WRT to reworking a step-through frame into a traditional diamond frame - well, it's doable, but unlikely to make any financial sense.
It'd provide some nice work for a frame builder and his painter, but it'd cost more than buying a frame to your liking instead.


If you want to avoid scrapping a frame you'll simply have to hold onto it until you find someone willing to take custody of a step-through frame. Or build it up and hope to be able to sell it on.


I have no issues with using step-through frames for casual riding.
And I bet no one will care.
Ride more, fret less.