It's scary, but I can somewhat believe the changing eye color thing. A person near me had gray eyes, 100% sure about that. There is an oil portrait of him as a young boy with dark brown eyes. His siblings claim that the painting was correct and that that person really had had brown eyes as a child. He was a very messed up person but not evil. Take this for what it's worth. I think there's a significant chance that the painter made an error and the siblings never paid proper attention to their brother's eye color.
This reminds me, and I understand I may sound like I'm LARPing, but I've also had my eyes change as noticed by other people.
Meeting family again after several months:
Close person: "Anon, your eyes have become darker."
Me: "No, that can't be true."
An even closer person: "Yes, it's true. They really are darker now; I can see it."
Then I look at the mirror and see that my eyes had really become a much darker shade of gray. (The change was permanent.)
The only notable new thing that happened to me during that period of time is that I became a Christian, started going to church, and threw out the Tarot cards. I had mildly spoopy experiences relating to that last part. I came to understand that the Tarot cards really are demonic in the way that results better than random chance come from telepathic demonic influence akin to channeling.
I'm reminded of the traditional representation of the evil eye as blue. Maybe it's not just about blue eyes being rare in those countries.
As a contrasting point of view, many children are born with blue eyes that later change color much like blond hair in children often darkens. Despite modern usage the "baby blue" in children's eyes is a dark shade of blue.