The main thing I think on is if they graphically update the silver covenant to have that "old high elf" feel, she'd look way too much like her sister Alleria.
It'd probably be doable, but it would be something to keep in mind. Main characters need to look distinct. Maybe keep the light blue tint to her clothes and the lack of hood. Maybe tweak Alleria slightly in her normal form to feel more like the leader of the void elves, with her tattoos and eyes going purple or something. Just so players can look at a glance and go "that one's the void elf leader" and "that one's the high elf leader."