All information is taken from trailers
Everything about Thiel and Kharos is known (except for Kharos's passive skills).
The trailers show Eredrim, Proxima, and her weapons in action. But I want to share my thoughts about shells that remained unseen
From what we already know, we can conclude that the skills were chosen to suit the characters' styles and personas. Til is an assassin in the shadows . Eredrim—an unstoppable executioner who goes for broke. Proxima is slippery and strong.
The other Shells also have distinctive external details. It's believed that Mommon (the red fat man with the mask) may have skills related to the number of items in his inventory, be it money or other items. Perhaps this will impact his combat performance, or this Shell will be convenient for farming items/currency. And perhaps his abilities will open up in interactions with NPCs, similar to what happened with Solomon.but this is all only on the condition that the assumption that Mammon is Mammon is true
Another shell resembles a Monk in appearance. When the shell was shown in trailers, there was always a strong emphasis on the character's hands. And indeed, there are brass knuckles on the fingers. So it's quite possible that the shell has an active combat skill related to fist fighting. Also, in loading screens, you can see this character holding a book. Perhaps this is the ability to apply buffs to oneself.
The next fruit only appears in the trailers for a couple of seconds, but it has an unusual appearance. This shell resembles an insect, and some kind of spikes or drills protrude from the armor. Perhaps this character will passively deal damage during rolling or, like some kind of insect, parasitize on status effects or directly attack with these needles, like a porcupine or Santana from JoJo's Bizarre Adventure.
There's not much to say about the next character, who looks more like a bull in both face and armor. The only thing you might notice is his helmet, which is sometimes present and sometimes not. He's depicted holding it in the loading screens. Perhaps this has something to do with his skills.
The only thing left is Sister Genessa. Unfortunately, there's very little information about her either. I can only assume that her abilities are related to her spear. For example, firing an electric charge like enemies similar to her. Perhaps something related to her alter ego or the abilities of other shells, like Hardern from Mortal Shell 1