It depends how the mangaka/author want to create their universe bc omegaverse always have different development from each of stories which are created by the mangaka/author. So there's no definite rules for omegaverse actually. They can develop depending on the author. :)
Did you know Beta can turn out to be Omega (づ ̄ ³ ̄)づ
At least that what happend in some manga i read before