My opinions on all the 2.0 characters:
Can double jump and float. Fair enough. Very enjoyable character to play with. I love the star power mechanic with the starbits! Makes for fun gameplay decisions and feels great to use. The downside of this character: The fireball lock-on ability. It's impractical and feels awkward to use in every way. Can you even cancel the lock-on without going far enough away from the enemy?
Another double jump and float character. His abilities are straightforward, easy and fun to use. One of the best characters, doesn't really have a downside. Should be fun to make levels with him.
Is slower than Mario, but otherwise similiar. His special ability is the shop which lets you buy items for coins. How cool is that?! Makes for some great gameplay and it makes you really wanna collect coins. If he has another special ability, I missed it. A downside is that when he is big, his sprite is so fat it looks styleclashingly weird. Still, great character!
Can recruit (some?) enemies by punching them and use them in battle. Nice and fitting mechanic. The big downside: His attack is terrible. Absolutely stupid. It's slow and after using it you can't move for a second. What's worse is that you have to use it whenever you want to run. Feels really bad and I really hope no one will use him.
Wtf is all I can say xD Styleclashing sprite aside, his gameplay is not fun. You get seen by any enemy (i assume) and it'll spawn a lot more enemies out of nowhere. His standard attack isn't so great, but at least he has interesting weapons. Didn't get to try everything though, because I can't stand his gameplay.
Finally another character with Mario-like physics. Has a really awesome and thematically-fitting high jump. Then there's the ocarina abilities though.. She can get unlimited use out of any ?-block, savestate her position and savestate enemy positions. The ocarina is just weird and makes for awkward gameplay. This character is fun to use, but her ocarina should make it very challenging to make levels with her.
Great character! He works just like in his games. I like pretty much all of his abilities and mechanics. I like how his accelleration is instant, both on ground and in mid-air. I guess his projectiles make him OP in normal Mario levels, but should be fun to make levels for him.
Like Megaman, she works just like in her games (i assume). Never played Metroid, so I can't say much. Her mechanics are complex. She seems to bring some unique abilities. Not too much of a fan of her gameplay though, but that's just me.
Has a double jump that lets him/her fly a bit. Can lift up enemies and throw them or use them to jump higher. Very fun gameplay! Now, wether I like or dislike this character I can only say when I know his/her interaction with other enemies, besides those fat things. If he/she can pick up ANY enemy, it's too OP for my liking. Should be fun to make levels for this character though.
Who even is this tiny person? Why does she have so weird powerups? I'm stuck in her level at the very beginning. I can only get wall-climbing and an umbrella.. This character needs an explanation. I don't know what to make of this.
Here we have a character similiar to Link. Nice! I wish his mid-air sword attack wouldn't take away all of his momentum, but when he has a power-up it's somewhat alright. He doesn't seem to have anything super special going on. A bit boring, but good alternative to Link.
Stop dressing up as a woman, Mario.
The best one of the characters, in my opinion. I really like how this egg feels! It's like I'm playing as an actual Yoshi egg.
Also everyone feels so slow compared to Mario. Definetly takes away from the fun. But here you go! My opinion on all the characters