I have two examples of this.
https://wowpedia.fandom.com/wiki/Anarys_Lunastre
Anarys is the same gender as the player. You use them to create your Nightborne disguise in Suramar.
https://wowpedia.fandom.com/wiki/Uncrowned_Peacekeeper
Uncrowned Peackeepers are also the same race as your character.
So this is a cool mechanic. Does anyone know of any other npc’s like this. Obviously, npc’s like this probably won’t be featured much.
Well, there is also the most obvious “alternate timeline you” that appear in the primalist future in Valdrakken and also in the caverns of time.
If you took her down in the Burning Crusade raid, Vashj compliments you on managing it when you meet her in Maldraxxus.
There are a couple of NPCs that address you by your earned PVP rank if you have any.
Also Dragonblight for the two quests from Chromie. Those being future then past you.
Xe’ra also has different dialogue leading to and after the quest where you play as Illidan for a reenactment of his encounter. Those being
Non-DH, killed Illidan on character
Non-DH, haven’t killed Illidan on character
DH (same regardless if you killed him on character).
Neither of those change appearance based on your toon.
They change dialogue though.
Not what the thread is about though. 
A change in dialogue is still a change.
Still not what the thread is about 
The thread is about change.
It didn’t restrict itself as to what type of change.
The OP literally states a couple NPCs that change their race depending on the on you happen to be playing
But continue posting things irrelevant to the threads you’re in. Seems to be your thing anyway
in fairness, the “how” of the change was ambiguous based on the original post. i don’t think drahliana’s first read of the question was, like, the wrong one; op clarified only later what he meant
Suppose that is fair. 
I could see how it could be ambiguous. Perhaps it should’ve said “Change based on your character’s characteristics,” but I thought that was too long-winded.
yeh, not tryna be combative, i just get the sense that drah wasn’t trying to be difficult. honestly, considering how badly the rpg elements of this “mmorpg” are implemented, even dialogue changes to reflect one’s character seem few and far between, so i thought they were fair game too
nah, honestly, my experience with the forums so far is that being as literal and detailed as possible is often a good vibe; i feel like there’s a diff between being long-winded and being meticulous, y’know?
No worries bud. I’m just tired and a little combative about certain stuff for no reason
Sorry about it
Would NPCs whose attitude and dialog change based on the Player Character count for this?
Sylvanas Loyalist Horde players get a unique interaction long after BFA ended, as Sylvanas acknowledges them as the closest thing she has to true friends after everything a part of herself had done.
Already mentioned is Xera commenting on whether or not the player had ever beaten Illidan before. I forgot I had done the raid years ago, until she reminded me.
I’m talking about npc’s themselves changing, not their dialogue. Otherwise the thread would be impossible to fill.