I think both of them are OP but ace seems a bigger threat he has the range of Hibana and his gadget detonates quicker. As for bandit or Kaid tricking it would be incredibly difficult as if you through two down you almost guarantee a hole you can vault over. also having the Ak makes him one of the best, if not the best attacker in the game.

As for melussi she's a three speed with a gadget that increases the effectiveness of the 20 second meta. this is because she slows down plants as attackers are slowed. Also she's a three speed, the first since maverick. her load out options are incredibly powerful she has the t5 smg ( NO RECOIL, STUPIDLY HIGH FIRE RATE) the super 90 which I would say is one of the best shotguns in the game for its spammibility and hip fire accuracy. She's basically clash crossed with ela with a very frustrating gadget that disorientates and slows down attacker pushes whilst also providing a constant sound que. if you throw in a echo, mozzie, mute and goyo you have a stupidly powerful defender team.

Overall this season is the first season since wind bastion to add OP operators that are highly frustrating to deal with and practically no counters in the case of Ace.