Self-hating
Motivated by societal distress caused by being female. Lesbians, tomboys and/or rape victims. The most known and arguably common type. Most of detransitioners come from this group.
Sexuality: Either homosexual ("straight" for them) or so obliterated by trauma so as to be completely non-existent ("asexual"). If not asexual, then either masochists/submissive, or "vanilla" (not perverted).
ID: Most are "men", but there is a significant minority of those who ID as sexless (agender, nonbinary, neutrois etc.). They don't really want to become men, as much as they want to stop being women.
Detransition rate: Very high. Feminism empowers non-conformists, lesbians, and victims, and so serves as a safe place for them to go. Furthermore, the general society views "I just wanted to be accepted" as an acceptable feminine motivation. The one exception are those who are 10+ years into it, didn’t get any nasty side effects from procedures, and have a partner and a job. They'll stick with the devil they know.
Common mental disorders: Anorexia, dysmorphia, anxiety, depression, autism.
Interests: Vary a lot. Plenty of quiet, bookish types. Often some sort of stereotypically masculine sport. Not that many of them are otherkin or furries, but plenty are therians. They often shun stereotypically feminine hobbies they genuinely enjoy and push themselves into things men in their lives do.
Transition: Baggy clothes, short haircuts, binding breasts. Normal male or unisex names. Hormones. Mastectomy and hysterectomy are common, but phallus is usually not constructed. They mumble something about “not good enough yet”, but it’s actually because they want to desex themselves and find penises disgusting.
"Goals": Either a normal, respectable dude, or a sexless being.
How to approach: Gentle conversation is the best. Affirm that loving women is okay, that any "masculine" interest is cool, that she didn’t deserve her assault/trauma – without calling her a woman outright. She has a lot of baggage attached to that word. Slowly build a friendly relationship, gently bring up side effects of hormones and surgeries. Once you see doubt, direct her towards detransitioners.
Kweer
Motivated by desire to be special and shallow aesthetics of the gender-special movement. Often there is a mild autoandrophilic element (caused by too much yaoi).
Sexuality: Straight (or "uwu gay boys"). Some of them identify as bisexual, but it's hard to determine if it's genuine bisexuality or attraction to manly men and she/her "femboys". Fetish-wise, into a lot of weird stuff. Furries, tentacles, latex, transformation, this sort of thing, often as a switch (both the doer and the target of the act). Sometimes come across as pedophilic, due to inappropriate conduct around children, sharing NSFW information with them etc. This, however, usually comes from the "sex positive" ideology, rather than genuine pedophilia (this is more of a "predatory" thing).
ID: Actually, a minority of them are "men" (I’d say 20-30% ). A lot of them call themselves half man, half woman (bigender, genderqueer etc.) or "genderfluid".
Detransition rate: Complicated. Young and "out" only on tumblr? Will go away. 25+ and a head of a LGBTQRSTUVWXYZ organisation? Not likely to back down. With every IRL thing done in the trans direction (coming out, hormones, surgeries, legal stuff, joining organisations), the chance of detransition drops significantly.
Common mental disorders: Narcissism, borderline, schizotypal, maladaptive daydreaming, sometimes a mild form of psychosis.
Interests: Cartoons, especially anime, drawing, making jewellery (with various obscure flags, to sell on Etsy). Lots of them are otherkin – the more special, the better (fairies, dragons, deities etc.), furries are also well-represented among them. Some of them are self-proclaimed witches or "spiritual" types. Overall they have a very poor relationship with reality.
Transition: Loads of flag patches, colourful hair, either binding without packing or packing without binding (uwu androgyny). Batshit insane names, often neopronouns. Further transition varies, from all the way to "my body is a boy’s body because it belongs to a boy!" Often get tattoos and piercings.
"Goals": Feminine bottom gay boy, handsome-but-still-pretty top yaoi boy with a hairless body of a Greek god, or a sparkling hermaphroditic alien who is adored by everyone.
How to approach: Don't feed her delusions. Don't give her undue attention. Allow her to talk about her gender fluctuations and kin memories, and just go "mhm". No "omg, you're so valid", but no "you’re fucking crazy". Include her in women-only spaces and events, keep her away from [BEEP] spaces/websites. Practical activities, like horse riding or camping are great ideas. The younger she is, the easier for her it will be to shake it off.