I know when I first started reading ABO stories they would have explanations at the beginning showing that female alphas also had penises. That way they could have alpha female x omega male/female pairings with the omegas having children.
I've never read any of Zigs novels though, so I don't know if they actively say that female alphas don't have anatomy like that, but I don't remember it having been mentioned one way or another in the manhwas of theirs I've read ...

I actually really like this story of Zig, I mean in their story, the two of them don't seem to have a too toxic relationship and the two of them are above average handsome hahaha...
And honestly, if Joshua gave birth to Pete... His partner should be a man, right? Besides, Chase already knows that Pete was born by Joshua... Why do they still refer Pete mother's to him as (her/she)? Or maybe I misinterpreted their words?( ̄∇ ̄")