It was mentioned in another thread. But I think it can make a thread of its own, so I hope Qoray wouldn't mind my stealing his question.
Anyway, we have Astarion's vampire's bite, and apparently Karlach is going to have something burning. If our companions, like in BG1 & 2, do have their own unique skills, what do you think it would be, and do we even have sufficient clues for every or at least some of our companions?
Personally, I don't really have a guess, but I'd love to hear your opinions.
I don't mind at all, in fact, I think it is really nice you asked

That would not even have been necessary
I wouldn't assume that every companion will have an unique ability. Astarion and Karlach have them because of unique backgrounds. But not every companion necessarily has to have some unique ability.
Gale has the netherese destruction orb in his chest, so maybe he gets some ability that uses that, similarily to Karlachs infernal rage, because of her heart.
And for shadowheart, there was a recent thread that showed a buff called "Demonspirit Aura", that we can't really explain yet and might have something to do with Shar
https://forums.larian.com/ubbthreads.php?ubb=showflat&Number=858094#Post858094So the only ones really missing are Laezel and Wyll. I think it is highly likely that each companion will at least get a minor special feature to make them more interesting