Reading the article, it seems Quinn's reasons for being non-binary are more to do with avoiding stereotypes than believing they are not female sex. So fits fine with playing for the woman's team.
Indeed they are, as the quotes I posted demonstrated. It breaks my heart that Quinn feels the need to identify out of being female in order to be comfortable with not performing feminity. But I understand why. I hope Quinn is happy.
Quinn is, as far I as I can tell, not taking hormones and therefore at no advantage in that way. But the point is, if Quinn can identify as non-binary and play on the female team, seeing as Quinn does not identify as female, what is stopping a male who identifies as non-binary doing the same?