I like this a lot. Many game jam submissions make the mistake of adding unnecessary complexity to the main controls or main mechanic such as controlling two different characters, mirrored characters, etc. You guys go for a very easy to understand, intuitive approach and I think that is also echoed through the rest of the design.
The goal of the game is simple and it's finite. It's not an endless mode / horde mode, so I actually feel motivated to complete it! It's also not too long or too short, took about 6 minutes of non-stop gameplay which is really perfect for a jam game.
The art design is simple but it works well. The black and white colors make you stand out, but I also do wonder whether color would make the game even more pretty. Hard to say for sure, from my perspective. The characters remind me of Monsters Inc, which is a nice comparison to have. The music leaves a little to be desired, but it doesn't get in the way, so it's really not a big deal. I wonder whether or not you would benefit from some sort of camera shake, again hard to say for me; the game feels good as is, just a thought.
The game gets easier as you get more of the characters off of the screen. I like the idea of that because it makes me feel like the game is speeding up as I get further and further into it, kind of like a chase scene in a movie or something. However, in practice, it only speeds up once you are down to a few pairs of characters.
This is by no means a complaint, because I think the pace of the game is fine in general, but I do think you could lean into this pace progression even more. Maybe as more characters are off the screen, all the characters could start moving around more often or start running randomly at times to add to the feeling that things are heating up as you go further on.
Also, here's a few more things you might add if you continue working on the game after the jam, which I think you should because of the fun of this and the potential here. I think it would be cool to some sort of physical barriers like walls to stop you moving in some cases, maybe as you progress. Also, it might cool to have some enemies to run away from temporarily, like an enemy that runs at you for 5-10 seconds until it explodes; these enemies only show up every so often so as to break up the pace. As things get really close to the end, you could have many of these enemies show up while your remaining characters you have to match run away from you, so you have to run away from the enemies often and things get tense towards the very end. With more and more variation you could make this game go on longer, or have multiple levels where the first level is what you have here, and later levels have some of these mechanical additions like walls, enemies, evasive characters, and so forth.
Overall, really great submission all around. Sorry if I rambled a bit. I think you guys should rank very high in all three categories.
I would love to have your rating / comments on my game too, so I can know what to improve.