Wheatley:
Wheatley is talkative and friendly at first, although his main motivation in befriending Chell seems to be obtaining her help in escaping. He frequently second guesses his own decisions and is not especially assertive, always trying to persuade Chell to go along with his plans rather than demanding that she do anything. Despite his general indecisiveness, he shows initiative in seeking out Chell to act on his own escape plans. He is patient and, when his actions lead to unpleasant consequences, he is quick to take responsibility and apologize - although usually as a lead-in to asking Chell to go along with another of his plans.

GLaDOS claims that Wheatley was designed as an "intelligence dampener" whose function was to render her less intelligent, and therefore less dangerous, by generating stupid ideas. Early on, it quickly becomes obvious that he tries to act smarter than he really is. His attempts at "hacking" are generally inept or misleading; when sabotaging turret production, for example, he asks Chell to look away so he can "hack" the door by breaking the glass. He repeatedly proves incapable of solving easily foreseeable problems that come up during his escape with Chell, forcing her to work out the details. At one point, he unsuccessfully attempts to evade GLaDOS' detection simply by speaking with a poorly faked American southern accent, which he claims (on the basis of no evidence whatsoever) lies outside her hearing range.

Noddy:
Sleeps. All. The. Time.

Baba: (Abilties, not personality)
Can push blocks around to change the rules of the universe. For example, if ROCK IS PUSH, Baba (And subsequently everyone) can push rocks.
another example is: SKULL IS DEFEAT. Anyone that's living (anything that's you in-game) gets hurt if they touch skulls. (in-game, they die if they touch skulls.)

Scout:
Scout is a positive and easygoing cat. They are an avid hunter who is dedicated to protecting their colony's borders.
What scout likes/dislikes: https://cattails-game.fandom.com/wiki/Scout#Gift_Guide

Firey:
In BFDI, Firey spent a good amount of time arguing and slapping Coiny. Firey can also be quite forgetful; e.g. him not realizing that lava can kill Leafy in Insectophobe's Nightmare, forgetting who Leafy is in "Get in the Van" and events afterward. Though, by the end of Season 1, he seems to have developed more of a genuine understanding of his surroundings and interactions with the other characters, such as acknowledging his unintentional cruelty to Leafy and revealing his thoughts on the conflicts around him. He also displays signs of genuine sincerity, such as when he reveals his true feelings to Leafy about her.

However, from BFDIA onwards, Firey completely ignores Leafy and has a blank expression whenever in close proximity. The reason for this is currently unknown.

Wiki pages (where i got these from.):
Wheatley: https://combineoverwiki.net/wiki/Wheatley#Personality
Noddy: N/A
Baba: N/A
Scout: https://cattails-game.fandom.com/wiki/Scout
Firey: https://battlefordreamisland.fandom.com/wiki/Firey