Not sure since I don't know MC that well but
Sara - Shulker- inflates things, always angry
Natalie - Also shulker- angry, annoying, will fight her sister frequently
Avana - Bee, smol, friendly, likes flowers, beneficial to any environment they're in
Mikhail - Warden? Big, protective, not useless like the mob though
Mya - Giant- big (the mob is still in game so it counts) (I think)
Tittank(ette) - Iron golem- big, metal, protective
Miezth - Phantom- loud, annoying, useless
Audie - The player- chaos and destruction