Male Betas can impregnate a woman beta. And as for Alphas, they can impregnate their Omegas even if it is a male or female.
Alpha x Omega (Male x male or male x female)
Beta x Omega (male x female)
Alpha x beta (male x female)
But for some reason, in this story. Alphas and Omegas are high class. Where an Alpha should be matched with Omega and Omega should be taken by an Alpha.
Let's watch Jooin and Hyung (blonde guy) break this kind of stereotype. Rooting for them:))