Disappointingly cis-het LOL.

I heard that reception of this game in Japan has mostly been either quite negative, or quite positive. I got my hopes up about it, given the premise. My feelings fell somewhere in the middle, though.

The romance is relatively weak in most of the routes (a few of which don't even depict a kiss... which indeed, probably would have felt forced in some routes), and definitely second to the rest of the story, but that doesn't feel like such a bad thing in this case. The story was engaging enough for me to keep me playing until the end, but I was forcing it by the time I was halfway through. Notably, this game features eight love interests, which is a lot, so I think they did OK considering that.
Of the six character routes that are initially available, only three (of the player's choice) must be played in order to unlock the last three routes (including the grand finale). So if, among those initial six LIs, you find a few that you really aren't into, you will have the freedom to skip over them. I felt that each route contributed some bits of information (some routes more than others) to the overall story, but I could see it being fine if some early ones were skipped over.
I felt that all of the LIs were likeable (at least upon concluding their routes... I'm looking at you, Ayumu).

The "gender bending" really felt like a missed opportunity. It doesn't really apply to the romantic aspects of the game, which is odd since they are both big focuses of the game. There isn't much interesting going on here in terms of gender identity, and most of the male characters don't feel anything special about being able to transform into or exist as females. (It's really just their anatomy that changes – not their gender.) It's often treated as something to be embarrassed about, that's hidden. It's mostly there to create what's supposed to be an amusing scenario in which the main character is unaware of the LI's dual identities (which are entirely obvious to the player). Which repeats to varying degrees in all applicable routes and started to annoy me after its second occurrence. It gets old quickly, and I found myself wishing they didn't waste so much time on it, and instead focused on the plot or romance more.
Ibuki is essentially non-binary at least. 😅

I think that the majority of the CGs were of nice quality. Nothing super fancy. Most of the art didn't feel awkward. I feel that they made OK choices about which scenes to include CGs for... Some felt unnecessary, while other scenes would have really benefited from one.
I really liked a lot of the character sprites! There were a bunch of interesting, asymmetrical facial expressions. I was a little disappointed at the lack of inclusion of character portraits for the protagonist, though. And I know it's uncommon for games of this genre, but I would have liked the protagonist to be voiced as well.
I thought the voice acting was great!
The music was fitting and I enjoyed it during the game, but I don't think much of it stood out enough that I would listen to the soundtrack on its own.
The text isn't without typos, and the formatting of the text is disjointed in places, but there's nothing too grievous. The English is not a very literal translation, which differs from my taste — especially where the content is severely altered in order to be more understandable for a non-Japanese audience — but I think most players will be OK with it.

This game functions well as a VN. Players can access a flowchart to return to any part of the game they've played before, and can skip to next choice or next line of unread text (whichever comes first) instantly and with ease. Returning for different endings is a cinch.
Button functions can be remapped manually (there are no alternative presets).
Volume of voice acting can be adjusted as a whole and also individually for each recurring character (although the default volumes are mostly balanced and I barely adjusted them).
My main complaint here is that the Auto mode functions very poorly. I'm not a super speedy reader when playing video games, and the Auto speed was still incredibly slow even at its fastest. I'll be waiting too long for the Auto to proceed from an unvoiced section, meanwhile at the same Auto speed, I'll have unvoiced single word text boxes ripped away before I can comprehend them. I just kept Auto off the whole time I played, and that was fine for me.

As the player progresses through the routes, they will unlock little extra scenes that can be accessed from the ACTIVITY REPORTS section of the menu. These are neat. However, no indication is provided as to which of these extras have been viewed previously, which I found to be a nuisance.

I think there's stuff here to enjoy. I just don't want people to get their hopes up the way that I did. You can still romance the magical girl boys... but don't expect too much.

(Review edited upon game completion.)

Remember when Fire Emblem was about, like, war and politics. It even had commentary on human suffering and religion and discrimination and so on and so forth. Fire Emblem used to be good. It used to mean something.

(For a more serious review:

I'm not totally opposed to the idea of a trashy fanservice game that only exists as an anniversary title, but if that was the goal of this game then why waste their time with the brand new world and characters that no one seems to care about. Why not make it a series-wide crossover and include several characters from each game instead of only 1 character. I've seen a couple people say that maybe this game was only made so that they could sell more swimsuit alts in the gacha game and honestly that idea makes me a bit depressed. The idea of a series like Fire Emblem going the route of pokemon where new games are primarily made to sell merchandise is pretty disheartening. I'm not actually that pessimistic about the future of FE though. We know an FE4 remake is coming and I'm currently praying that the team that made 3H is working on that.)