It's definitely an interesting one. Ive played plenty of Fgs in my time, but this game, without looking at some wiki, I for the life of me cannot get an idea how to do elaborate combos, the best I can do is just string all three normals and then maybe some special. Pretty damn jank but honestly, still really fun to play.
The cast of character comprises from a wild selection of Visual Novels, so it's another one of many Visual Novel Fgs, which I love to play.
All around a pretty solid fighter, but does pale to majority of the more modern experiences you can get with other Fgs.

i was gonna like this game out of principle, since how could i dislike a fighting game where not only are ToHeart character's playable, but also one where tamaki is literally top tier lmao. turns out the game is actually just a solid fighter in general with some interesting assist mechanics, which i may not even fully understand completely (yet). i love the four button setup as usual and the special moves are easy to figure out even without a guide --though i do recommend afroshouji's gamefaqs guide if you're looking to play it. my only complaint is the difficulty of the final boss, since his assist gives him a whole bar of health after you've beaten him, but I think that complaint could be used for nearly every arcade fighting game.

Aquapazza is... a fighting anime game. I think for what it is, it's a fun little fighting game featuring anime characters from shows I've never watched, not to say those shows are bad or anything, just never heard of them.

I don't want to make my points too long so I'll just give a basic run down.
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The game is a fighter where you select a combat character and a support character, there are a total of 26 characters, 13 that are playable in terms of combat, and 13 that are just supports.
The game has it's own unique super moves and ultimate moves called Splash Arts that make the game fun.
The game also does the cardinal sin most fighting games do in which they make the final boss (or bosses) unfair cheap pieces of annoyance for the sake of extending gameplay time, causing you to have to cheese the boss.
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I think it's interesting seeing a fighting game like that of unknown/not as popular IPs as say "DRAGON BALL, ONE PIECE, JOJO, NARUTO, etc" getting fighting games or games that aren't just "visuals novel games" really allows for variety, especially since I'm convinced most of the characters are just from harem animes, or yuri animes which don't involve fighting... for the most part, I know there are some that do.
Overall it's a fine enough fighting game, it's really unique and worth picking up.
It's mostly likely never going to get a port or remaster/remake like say JOJO ALL STAR BATTLE R, so if you're interested in unique fighters like it, I'd say pick it up.
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I'm going to give it 3.5 stars cause I did have fun with it, nearly gave it 4 stars, but the final bosses are really REALLY REALLY cheap and unfair.
Still recommend picking it up if this game ever caught your eye. If you want more unique fighters I would recommend:

- JOJO'S BIZZARE ADVENTURE HERITAGE FOR THE FUTURE (PS1)
- CAPCOM VS SNK (PS2)
- CAPCOM VS SNK 2 (PS2)
- STREET FIGHTER X TEKKEN (XBOX 360/PS3)
- TATSUNOKO VS CAPCOM (WII ONLY)
- JOJO'S BIZZARE ADVENTURE ALL STAR BATTLE R (PS4/PS5/XBOX/PC)
- JUMP ULTIMATE STARS (Super Smash Bros with Anime characters)
and many others

Still I would recommend Aquapazza, it tries it's best to match fighting games like CAPCOM and ARC SYSTEMS works but falls short, but for the most part there is some enjoyment to get out of it, so if you're interested, I recommend it!