Yes, it is of course possible, but it's kind of hard to define what's natural eye color of an elf, since they always have their eyes affected by magic source they draw their power from. It's still beta, so it may not be even his final version, so let's wait.
My guess is that this color have something to do with death magic which is soaked all over shadowlands. Ysera also got new eyes in Ardenweald.
Either way, I don't think Kael's eye color will be of any importance for his future story.
I had the theory of blue being the natural color from quite some time, and the things that made me believe that are that when Blood elves were made playable, the high elves were added with blue eyes, and there was not a direct quote I were able to take from anywhere that said the blue color was there because of arcane magic, and in Vanilla/Classic, before the introduction of Blood elves, the eyes Thalassians had was normal human like eyes. On the other hand, we know very well from various sources that the green eyes were due to the effects of fel radiation, and the golden ones are there for light worshippers who draw the light from the Sunwell as some sort of belief system.
But I see a problem with Kael'thas' photo and is that he looks like an undead, or, by default, he has been changed, so... I would not take his appearance as some kind of reliable source of 'unbuilt' or 'deconstructed' Thalassian appearance or whatever is implied.
I'm bringing this up again because you and the original poster that I responded to never offered an answer. The elf in this picture does not have black pupils, and no high elf has ever had "humanlike eyes" with black pupils. They did not glow, but they are certainly not humanlike. If you'd like to see what I mean in case you didn't play during classic, this particular model appears at about 1:49 and again at 4:10: https://www.youtube.com/watch?v=Z1eI5l0nd38 (the video shows all high elven NPCs in classic).
Seems like they went for 'anime like' eyes.
That is, wherein the pupil portion is just a darkened color of the overall eye color.
I think what the others mean when they say 'human like' is that the eyes aren't like those of a Draenei/Blood Elf/Night Elf/Nightborne where you see no distinct areas for an iris and pupil - it's just one solid color.
Whether Classic demonstrated this well or not, at this point it doesn't really matter since the BFA Sylvanas flashback shows when High Elves were simply "High Elves" they had definitively human eyes.
Fair enough. If you watch the video, you can see that their eyes were not like anime eyes. There are no pupils at all, although there is an iris and a white sclera. Even the blue eyes of the newer high elf model does not have a black pupil, so I think the animated short was artistic choice and not necessarily because Classic was unable to show that they had eyes like humans with black pupils.
That's all for the moment...
Hopefully the wait won't be too long for the new customization options for Allied Races.
I feel like the blood elves and the worgen are really the losers.
PTR up, so changed my Mage into this look! Shadowlands going to be niice.
https://www.youtube.com/@DoffenGG
Gaming and WoW stuff
Small character customization update:
Dwarves got beards and mustaches split in this build! This small change to dwarven facial hair means they got their beard/mustache combinations up from 11 to 110 without a single new asset being added! I hope they do it too for dark iron dwarves, it would raise their facial hair from 7 options to 49 combinations.
Whatever...