It's interesting to note that the actor's pose shows a resemblance to Blackbolt, whose (http://i.imgur.com/c8OUWdw.jpg) photo is likewise shared by Comicbookmovie on its website.
According to (http://www.nydailynews.com/entertainment/movies/vin-diesel-hints-role-marvel-inhumans-article-1.2059577) New York Daily News , Diesel has been rumoured to play Blackbolt, the leader of the superhumans that make up the "Inhumans." The actor has so far been teasing his fans with the role but has yet to personally confirm his involvement.
Likewise, Diesel supposedly fits the role of Blackbolt because of his deep voice.