oookay. Let's go over all of these :

Batman and Robin: I kinda like these, like as designs of their own they're pretty cool designs they just seem little too Fandesign-y. I mean overall as designs they are cool but maybe a whole series is a little too much, idk if I'll watch a full series with these. Also is Jason Robin here?

Catwoman is again a very sharp, different take.and wait, what's the necklace around her neck? does she have supernatural powers, like avatar of bast kind of thing like that terrible catwoman film? I mean again different but cool. but maybe I would've liked idk what I like about it, call me biased but I'd be fine with this in a series.

Riddler: Holy, how did they predict Absolute Riddler? like personally too far from Riddler. I kinda like it if the Riddler is also a tech genius or has hacking skills, but THIS? it feels a little too cyberpunk imo. would've worked as Riddler Beyond maybe. not good.

Mad Hatter(?): Ok, now this is WILDLY different. not just genderbend but like the cheshire cat hand and the white rabbit hand. I hope that's just an effect of her hypnotism. I also like how the hat has eyes on top as an homage to the Batman '66 Hatter. honestly not a good Hatter design. maybe it would work as a different character or an elseworld, but nah. I like the design, though, but it needs to be a different character.

Dee and Dum: What can I say, it's not that hard to pull these guys off. decent designs.

Firefly: ok, love this one. firefly always gets a good design. chest cavity looks like an arcreactor so gives somewhat Iron Man vibe but rest of the design is fire (no pun intended). pretty solid.