Has your daughter started her periods yet, OP?
I wonder whether there's a way to let her experiment with different identities without making too much of a fuss about it, whilst teaching her to be positive about her developing body.
I started my periods when I was 13 and went on the pill when I was 17 and pretty much didn't menstruate again (or even really give it much thought) until I was 30. Then when I was TTC I read a book about tracking my menstrual cycle to maximise my chances of getting pregnant and I learned all about ovulation and the different stages of the menstrual cycle and this amazing process the female body goes though every month or so and I felt kind of sad that I suppressed that for over a decade, and silly for not appreciating how amazing the female body is. I found myself wishing I'd known all these things at 14, not because I wanted to be pregnant at 14, but because I didn't feel like I'd properly appreciated my body for all that time.
I wonder if there's a way to leave the gender stuff to one side as much as possible, but in the context of talking to your daughter about sex and periods, really help her to understand what the female body does and why it is so incredible. The book "My Period" by Milli Hill (who is a gender critical feminist) might help with this.
And similarly, her breasts will be growing, so perhaps you could encourage her to feel positive about them by taking her to get fitted regularly and buying her bras which she likes and finds comfortable. If you had a positive experience breastfeeding her there may be a way to drop that into the conversation at that point.
It might sound weird, but the detransitioned woman Chloe Cole, who had a double mastectomy at 15 and now campaigns against gender ideology, says that she was in a sex ed lesson at 16 and the thought, "I'll never breastfeed my child" suddenly hit her and that was the start of her realising she'd made a terrible mistake. If you can help your daughter to love her female body now and look forward to what it will hopefully be able to do if and when she's ready, she might think twice about hormones and surgery.
And of course, the clearer it becomes to her that female bodies are very different from male bodies and if you are one you can't become the other, hopefully it will eventually dawn on her that gender is meaningless and special pronouns are daft.