Best engine for a dance based game?

So, a while back I had gotten an idea for this hetero couple that has inflation as their kink; my main idea with them is to have the girlfriend fascinated with inflating the boyfriend through different means, who goes along with it while also having a few retaliation methods. This leads to a date night where they do a little “foreplay” in a similar vein to couples doing strip poker: a game where the losing party inflates while any bonuses the winning party scores causes extra inflation.
The idea came from a few images, a fic I read, and a game that I heard of that each had two players competing in a game, where the losing party suffered a dose of inflation in some way, shape, or form. I figured I could apply something similar to a dance game scenario.

The basics for the game is similar to classic dance games (think the arrow system in Friday Night Funkin for those who aren’t as old), however, the character models and how much they inflate is significant in how it interacts with the system; as the characters get bigger, it obviously gets harder for for them to move, so even if the player hits the appropriate keys sometimes it won’t register if they’re getting round enough for their legs to spread apart or for them to lose sight of their feet. This would include enemy AI as they would start to miss more steps.
Basically, as the characters grow round there becomes a chance that an input will fail to register, with this chance increasing as the models get bigger.

Now the bigger question I have is, what does everyone think would be a good game engine for this?
My main goals and ideas for this concept would be:
*A rhythm game in a similar vein to Dance Dance Revolution (so an engine that can background movements and player input, and can handle animations for a character model)
*A choice between two dancers, male and female
*Having both characters be inflatable
*A means of implementing a input fail method, like a chance system, for players
*Dynamic difficulty

Some bonus objectives would be:
*Multiple inflation types (weight gain, air, blueberry, etc.)
*Costume choices and clothing damage (a few ideas would be having a choice between clothes with popping buttons, full body outfits slowly ripping, snapping laces, to even simply shirts rising up over a burgeoning belly)
*A type of censor filter choice (the idea would be to have three options: one for partial nudity, one for no nudity, and one for COMPLETE NUDITY)

The main style idea I have for the game is 3D models with a cell-shaded look.

maybe too far fetched for body tracking, but you could use standard 4k-9k layout, should be doable in unity, godot or gms. Though you could try godot as it’s a simpler, lighter engine and is much like unity in functionality.

Yeah, Godot sounds like the better option since Unity’s proven to be untrustworthy now:

Even though they’ve walked back on the decision, they’ve already shown what they see gamers and developers as.

I’m fairly new to game development (like, so new I’ve only seen basic videos on developers making their own games), so I hope I don’t sound too obtuse when I ask what body tracking is.

Also, I’ve heard plenty about Godot but this is the first time I’ve heard of “GMS”, is that a newer engine?

GMS = Game Maker Studio, recently switched to a one time payment license instead of a subscription model. I’d still recommend Godot over GMS due to Godot being free, open source and supporting multiple code languages so you’re not trapped in GMS’s proprietary language should you ever want to move to something different.