Suki: either Japanese or Spanish- Cara just gives off the vibe of A: knowing Spanish and B: teaching younger Suki and Red Spanish- maybe even trying to teach younger Scorpion?
Red: Spanish. She would use it to swear or gossip without getting in trouble.
Paras: damn i never talk about them anymore- anyways they would (and I think I may just make this cannon) know French. And NO not because of their name.
Eden: would learn f**kin Latin or something like that
N0VAA: Binary /j
Mia: knows Sign Language and is trying to learn Morse Code. SL for being able to communicate without needing to talk and Morse Code because they think its cool
I for some reason can not remember any of my 90+ ocs right now so i will add to this list later