The story itself is good, but I find it disappointing that the main relationships we see are mostly in the form of crushes instead of friendships. I don't doubt for a minute the sincerity of the feelings presented -because the author is simply THAT good a writer-, but I would rather have seen them as friends for a few years before they became almost-lovers at such tender ages (eleven to fourteen).
I realize that teenage sexuality can and does indeed happen in real life at those ages, but seeing those specific Harry Potter characters (except maaaybe for Malfoy and some of the Slytherins, since we don't know that much about their private lives) behave that way feels very jarring compared to how they behaved in canon.
It all feels like too odd and convenient a change resulting from the butterfly effect of Harry being born a girl.
Also, Harry could come across as a Mary Sue (too pretty, everyone wants her, tragic past, powerful with unusual skills), but, personally, I feel that the trials and setbacks she keeps going through balance those traits out.
On the good side, the trauma fem!Harry and the others are going through and all the consequences developing from their experiences are very believable and well-written. This is an example of angst written well, in my personal opinion.
The story has a blend of a genuine sense of adventure, intrigue and magic that many stories in the fandom are missing and resonate very well with the reader.
Romance/sexuality aside, the characters are believable. Even when their personalities feel "off", they are rounded, tridimensional people, not just puppets going through the motions, simply there to move the plot along.
Anyway, this IS a well-written story. The warnings and 'Mature' rating are well-earned, but it's definitely interesting and different, and certainly worth checking out; just keep in mind that it has some potentially triggering subjects: violence, death, emotional, psychological and mental abuse, both implicit and explicit sex, non-consensual sex, minors in sexual situations, emotional angst, possession/mental-power-play, and possibly others I've forgotten. There is also het, slash and femslash thrown in almost everywhere, if that's something you care about.
Like someone said in the comments, good Fem!Harry is hard to find. This is one instance of it.