Big fan of the Blademaster, but I can only see it as a transmogset, or as a reward for a quest chain ala green fire. Yet, it could work for warrior, monk and rogue, so they can become a BM, with the transmog set, the title, and some spells adjusted, like bladestorm, Spinning crane kick and blade flurry to the visual of the blademasters bladestorm in wc3.
Problem, BM is more of a horde class, so there would be the mountain king for the alliance. but what classes would you add for other races? So pretty unlikely, sadly.