as much as i can appreciate and respect headcanons of genderfluid/girlboy/multigender shi qingxuan ....... i really think she's coded as transfem more than anything else. like lets first consider the way that others react to her girl-form, and to how others react to her trying to get them to join her in girl-world...
this comment during the banyue arc... it's referring to how xie lian is worried everyone will just blame banyue and let pei xiu off scot-free. but i think its interesting that qingxuan feels the "culture" of the upper court so keenly given that at every opportunity, she's described as being one of the most popular and well-liked members of the upper court. for most others, that would/does lend them to being arrogant and abusing their power, or at least worrying less about those who are likely to experience the short end of the stick. but i think because of the way qingxuan is mocked/bad-mouthed for liking her female form so much, she understands much more than others assume she will.
and then there's this bit from "ming yi" being upset about being pushed to use her female form. it's clear everyone can use any form they like, but most just use the one they're comfortable with. i think it's interesting(and very telling) that "disgust" is the operative word here, given that the transmisogynistic boogeyman of the "yucky man in dress" is the most common way we see trans women maligned in pop culture. this + the bit from shi wudu (below) i think really both show that it's not just general 'queerphobia' that shi qingxuan faces, it's transmisogyny specifically. or at least, it's definitely transmisogynistic in nature, whether or not SQX is "really" a trans woman or not.
again, "disgust" and "disgrace" are really interesting operative words here. shi wudu is clearly transphobic, because "I dont care what appearance you prefer" is bad regardless of the reasons SQX has to change between male and female forms. but i think the last bit, about her being afraid of him, is huge. personally, i think she would be in her female form even more often(maybe.... forever) if shi wudu wasn't pressuring her to use her "true form"(does that remind you of anything? because the use of "true form" makes me think of, like, "biological male" stuff. "youre not a real girl"/"youre still a man in a dress" type of arguments. implying that her "male form" is her true form, and disregarding the fact that shes literally more powerful in lady form... its so transmisogynistic).
it really seems that her true wish is to be in her female form, and everybody around her is constantly pushing back on that, with as much pressure as they can. however, she still uses her female form regularly, despite all these comments/harassment-- because that's how much it matters to her.
AND! if alllllllllllllll that isn't enough, well. in the donghua, her "male form" just is dressed in green, not surprising, wind master, etc. but her female form dresses in the colors of the trans flag. i genuinely don't think it could be any more obvious
shi qingxuan is a trans girl!!!!!! its just the truth !!!