Normally, I tend to avoids ABO stories. I find it like a cheap excuse. A marriage between two women in Omegaverse can be glossed over as straight marriage. In fact, it is.
An omega paired with an alpha because that's how it's 'supposed to be'. How is that any different than the justification for straight relationship?
There's some exceptions, though. Like this one. The omega protagonist gets to know her love interest under the assumption that she was an alpha, it was because of some lingering pheromones to boot. But the protagonist doesn't gives up in pursuing her love interest, even after knowing she's practically is a beta. This alone has thrown away the stigma carried over by the ABO setting. I can enjoy this kind of stories.
Her resolve to stay true with her love interest, even after finding out that she was only fallen in love because of some leftover pheromones, is just icing to the cake. A very well done twist ending, and in a good encouraging way.