Azdaja's eyes are blue and cyan, which as far we know, do no relate to any trolls... But at the same time, the opposite of red is cyan, maybe the cyan eye is defective? Because for Sollux, Mituna and Psiioniic, they were blue and red

I mean, every Psionic we have seen so far has had different eye colors! If anything Cyan may relate to the fact he’s Mindbound? We don’t quite know how relevant the Eye Colors are, if they’re relevant at all. Except the black, that is, Folykl is most likely blind.