Just like the title says, I'm looking for a long lost game from back in the days. The plot was essentially men versus women for world domination. I wish I could even remember who made it.

My ex made it, but I don't know the title.

I assume you mean this game, Mobygames is usually a good site for information about old games (IMO).

Yes! I'm having trouble finding a working version of it where some shady site isn't asking for CC or PP information... wish GoG had it!

Well you can vote for it on the wishlist, but that doesn't help your current situation ;)
I haven't seen it on sale digitally anywhere (not that I've really looked) so I'm guessing you'll either have to buy it on CD (Amazon, auction sites and such) or get it illegally.

Yep, the last time I played I had it on diskettes.

I think I ALMOST remember this one - is it where the lil' people looked almost like the characters in Lemmings? And was gameplay similar to Syndicate (iso-ish perspective, control of small squads of male or female?). And for some reason I also feel like you could change the sex of your characters - am I way off here?

Definitely not it, but the theme is quite similar, and you can find it right here on GOG:

Rex Nebular and the Cosmic Gender Bender

(not sure of how big you are on point & click adventures, though)