Well, Jaheira is a half elf, and her human half is presumably Tethyran (if that’s the right adjective), so even if her elven parent were pale that could explain her more olive complexion in her BG1&2 pics. Assuming she has one elven and one human parent, and not two half elves. I’m not sure if we know?
"You may call it 'nonsense' if you like, but I've heard nonsense, compared with which that would be as sensible as a dictionary!"