None of the characters feel bad to play nor do they feel under powered, which is great. However, there are a few things which I think could improve balance and gameplay.
The dash mechanic is a welcome one, however feels too strong seeing that it can allow a player to get out of numerous character abilities. I'm not sure what could be changed about this to make it better, and it's certainly not a detriment to the game.
Daemon could do with a small decrease to his general damage, otherwise he is completely fine.
Nidhogger can cancel out of a few animations whilst still getting the attack off, which is allowing for him to chew through characters in a way which feels unfair if you end up against him alone. Making him not be able to cancel his animations would promptly fix this.
Maeve's main issue is that her cage feels unfair to play against, mainly due to not being able to do anything to counter it, especially seeing that she's unable to miss it. If she could cast it and possibly miss it, or it could be damaged so people could break out, this might change how it feels.
Kulev's Sacred Ground could do with a buff, as it's healing does not feel strong enough for him to be viable to the team as a single healer, that being said, this only needs a small buff as I think it could easily be made too strong.
Zerocool's healing is absurd, I've played games where 3 people cannot kill someone being pocketed by Zerocool, and his mobility makes him hard to kill. A reduction his healing per second would certainly improve this as I think his mobility is a fine thing for him to have and gives him much needed survivability. Alternatively, if he was less mobile while healing, this could also fix the problem.
El Bastardo feels too sustainable, his shield mechanic is way too strong. A nerf to the shield mechanic would make this better to play against, as he's able to draw shield from everyone he hits and is able to hit multiple people at once which makes this get insane pretty fast. Additionally it feels like his bounce tracks the player, which I think should be changed to make it a bit more fair considering it is a stun.
Buttercup is well balanced in most aspects, except for her CC potential. I think her slow on her oil spill ability is fine, but the stuns I think could be removed.
Makutu is all around a fantastic, however I do think that the stun from his barge should see a small increase, as it currently feels nonexistent.
Otherwise the game is great to play and me and my friends are having a lot of fun playing it! I am looking forward to seeing more maps, characters, and hopefully game modes once the game is released!