User blog comment:SquirtyEatsapancake/things I just noticed/@comment-36899643-20190625012830/@comment-38126337-20190627122604

Well making her eyes blue and making her look dark in the shadows in the woods to make her look like a "beast" is what the animators thought would look good. Remember, up until she was shown, only stuff about the amphibians were shown so maybe they saw her with blue eyes to look intimidating!