Let me guess; it also asked the House Elves to replace Harry's uniform etc with the 'correct' version.
Hogwarts uniform is robes, and those are fairly monogender as clothing goes.
As Hermione said, Harry already had to get the girl styled robes, though Harry's young enough for the differences to likely be minor, so there is no need for the house elves to do anything about that. As for Harry's other clothes, as Harry thought about it, Hogwarts doesn't seem to care what is under the robes, which must be worn at all times on school days(with a possible exception for after the last classes of the day).
This chapter was full of typos, but i didn't care enough to pick them out, sorry. I'm going to guess the constant -and at times mid sentence- changes in pronouns were emblematic of Harry struggling with adjusting to his new biological situation. I do particularly like that this isn't "can never be undone!!!!" so many changed!Harry fics go for, instead being, "We could risk your life trying to break the spell now, or let you wait five years for the spell to break safely on its own". It's practical, pragmatic, and lets there be an established lore about people having lasting changes, making things like "coming out" have, potentially, a very different subtext.
Whether Harry winds up preferring to be female or develops any attraction to boys, girls, both, or neither isn't something I expect to show up for a long time, if this fic ever gets that far.
This reminds me of
https://www.fanfiction.net/s/13230340/1/Harry-Is-A-Dragon-And-That-s-Okay in which, at some point in kindergarten, Harry one day woke up as a dragon. Why? Never really even speculated on. Harry being a wizard attending Hogwarts with a wand, while technically being non-human, lets Dumbledore make some changes to laws that let him start teaching more and more varieties of formerly barred races attend school. It ends with Norberta becoming the first natural dragon to attend classes. Permanent voluntary sex changes are just one of many things that come up in the story.