It always feels weird when people act like eye color is super obvious. I couldn't tell you what color Rou Ran's/Loulan's eyes were, or Shi Sui. Hell, I couldn't even tell you what color Maomao's eyes were without double-checking. I could at least tell you Jinshi's eye color, but only because they match his hair (purple).With the first episode of the second season having come out on CR, I had noticed that Shi Sui had the same colour eyes as Loulan (the first season put a lot of emphasis on Loulan's eyes, which at the time I thought was odd). Now it makes sense.
Anyway, hints based on eye color might as well not exist, for me. (For the anime, not the manga, obviously.) Hair color: yes. Eye color: no.
Though in the case of Loulan in the first episode of the anime, they had the lighting such that it changed the color of her hair (yellow lighting plus shadows), so that didn't trigger notions of similarity either. And all of her ladies-in-waiting (the presumed stand-ins) have brown hair, which also doesn't match Shi Sui's.