The movies are Star Wars, Empire, and Jedi. That’s what they’ve been called by everyone, so that’s what they will be called.
The original copyrights I believe are register under SW, TESB, and ROTJ as well, making those the official titles
I won’t discuss it for SW, because this is its original title,under which it was first registered. But for the others, what is the copyright ? TESB and ROTJ were marketed as “SW : TESB” and “SW : ROTJ” but the episode number was originally in the crawl.
Don’t know if this is entirely reliable, but here is imdb card : http://www.imdb.com/title/tt2488496/releaseinfo?ref_=tt_dt_dt#akas
(original title) Star Wars: Episode VII - The Force Awakens
(alternative title) Star Wars: The Force Awakens