Eye color genetics is definitely weirder on Roshar than here, but I’m not certain it would prevent someone from being born with different color light eyes to two lighteyed parents, for instance. Apparently lighteyes and darkeyes genetics don’t often mix to produce full lighteyes, though, I did find that much:
https://wob.coppermind.net/events/148/#e2782 (Last section)
We’ve also been told eye color is related to the orders originally, though not that connected today, and for instance, Kaladin gets blue eyes because he’s a Windrunner, while other Orders get different colors it seems. So I would guess there’s some genetic weirdness to it.