Yuna's eyes are also briefly gold during the scene with the flowers, when she's laughing at Zatan spitting one out. Gold probably means amusement. Hazel is probably unsure or mistrusting; she flashes the same color during the bunker sequence if you choose to approach her first and then retreats without offering her hand. Green might be considered her default state for lack of a better word, or could also be considered content or neutral. Grey seems to mean depression or distress. Red is anger and aggression. Pink is embarrassment and probably lust unless she has a specific variant for lust we haven't seen yet. I doubt blue means love; considering what memories she's sharing, sadness could be a better guess. Or perhaps vulnerability and/or trust - Yuna's eyes also turn blue if you allow her to approach in the bunker and then accept her hand when offered.
Sonmi seems to be in a permanently depressed state at the moment. Far as I could tell her eyes haven't been anything other than grey. She seems regretful if Shani thanks her for saving her life and asks if there's somewhere she's needed, but it's difficult to judge how hard that hit her when her eyes didn't shift along with her facial expression. Possible that Shani could get closer to her than Zatan could if she doesn't see Shani as the same kind of threat.
Regardless, Yuna is best girl and I look forward to more of her. Definitely the character I'm most interested in story-wise.
