For Skyrim Bethesda used the Trailerkiin/Dovahkiin i.e. this guy:-

http://img4.wikia.nocookie.net/__cb20120123065657/elderscrolls/images/thumb/f/fc/Dovakiin_DRAGONBORN%21.png/1000px-Dovakiin_DRAGONBORN%21.png

and for Oblivion we got a quick glimpse or two of this guy (The hero of Kvatch):-

https://www.youtube.com/watch?v=qJnnPh44Rlo(0:57)

http://img4.wikia.nocookie.net/__cb20140427115244/elderscrolls/images/3/38/The_Hero_of_Kvatch_in_Imperial_Dragon_armour.jpg

I'm wondering are there any promotional nerevarine references out there? Perhaps a certain face/race that Bethesda have used as the pc during gameplay videos like they did with the trailerkiin in Skyrim?

The wiki seems to suggest that this guy from the back of the Morrowind box may be the promotional Nerevarine but I can't seem to find him anywhere else:-

http://img2.wikia.nocookie.net/__cb20140717042737/elderscrolls/images/b/b3/Morrowind_Dark_Elf.jpg

Sometimes I like to play as these types of characters when I'm doing a proper canon playthrough of an Elder Scrolls game which is why I'm asking.

Since the Nerevarine is an Ashlander character or prophecy, then a Dunmer would be more lore correct in the strictest sense. But that is not to say that any outsider would not be the hero. Note all Dunmer not from Vvardenfell are considered Outsiders, not just the other races. So, any race can be the hero obviously.

As to your original question, back when they were making Morrowind they were just hoping someone would buy their neat game, so they did not have as cohesive a marketing plan in place as they do now. So, that guy on the box was just someone from their artwork concepts, and not something you can exactly recreate in game. Although Dwemer or Chitin Armor would be a good place to start to make one that looks like him.

Yes I know what you mean. "Outlander" seems to be based on accent and people not recognising the PC in Morrowind it seems whether he's Dunmer or not. I agree though Dunmer does make the most sense as otherwise people would surely react in shock at another race being the Nerevarine yet they don't.

Actually I think you can create him perfectly in game. I have taken a look just now and his face and hair are available. I'm still looking around now to see if I can find him used anywhere else.

This quest is the one that has the Dumner in the gear

Do that and you get the armor, then all you need is a two handed sword and your set. Note I think they are standing there even before the quest starts, so you can look at the armor before getting involved.

Thanks very much, I'll look into that soon. Yes he seems to have bonemold armor with a cloth bracer on his left arm and a Daedric Shortsword. I haven't played Morrowind in about 8 years so it'll be an experience to get back into it now.

The main thing I dislike about being a Dunmer is the fact that every single male face seems to have been used by someone else in the game. It kind of kills the immersion when you bump into someone with the same mush as you every now and again. I wish they would've put a unique face in there to use. Still my favourite Elder Scrolls game though.