May I direct you to my thread about the void aspect?
I’ll have that Sunwell if its the last thing I do! twirls villain mustache
(this is a joke. >.> I’ve learned I have to say this with some of these.)
Shadow priests of any race aren’t literally infused entirely with the Void. They just use it.
Nightborne are an additional offshoot of Night Elf.
Aszhara was a night elf of the highborne. While she and her group became the Naga thanks to N’zoth, it was highborne rebels who would later become the High Elves.