Seconding this, and also the advice to approach Bayswater, and the observations of the teacher upthread who linked autism to self-harm and also same sex attraction.
There are also a lot of threads on the Feminism board that may be of use/interest.
My experience, or one of my experiences at least, is that autistic children who are loners and don't fit in often gravitate towards the LGBT+ crowd because they get acceptance. Plus I think autistic kids struggle to process same sex attraction ("category error") and get sucked into online crap about how that "must mean" they're "really" trans.
Also, regarding gendered artefacts (hair clips etc) my experience of FTM trans kids in one of my DC's social circle is that they end up taking testosterone and growing facial hair, change their name to boys' names and expect everyone to collude in the fantasy that they're male, but they don't seem to change their behaviour from stereotypical "female" behaviour and hobbies etc. So they wear pink and have flowery tattoos and do crochet and knitting, and seem to think that makes them appear as gay men. They are also pleasant, well socialised and not above doing domestic tasks, unlike their MTF counterparts! All a wild generalisation of course, but the whole thing seems to be about taking wild generalisations and pretending they're the begininng and end of reality, to some extent.
I have a MTF trans child for context, and we have really been through it as a family. Sending love and strength to you OP.