The Dunmer accent can range from modern “posh” British accents to the Trans-Atlantic accent from early Hollywood. To keep from sounding distinctly North American, Dunmer voice actors are asked to avoid the rhotic R.

In general, Dunmer should sound wise, even in their youth. They live in a harsh land, and their lifespans are very long - they are a pragmatic people and venerate the wisdom of their elders from even from a young age.  They should speak in a precise manner, clear and articulated, taking the time to think through exactly what they mean to say as they say it.

For males, the rasp is the most important thing.  If you can throat sing, and apply this rasp on top of throat singing, that is the ideal Dunmer voice. That's how Jeff Baker does the voice.  

Voice Type Noble, leader, and diplomat. He is respected and politically powerful. His voice is smooth and smokey, mid-toned rather than particularly deep or high. Has a condescension about his tone expected of his position and authority, but doesn't speak with malice - just with the simple fact that the player is beneath him. (Lord Vetinari from the Discworld series would be a character reference).
Requires the classic Dunmer throat singing/rasp.