As we previously reported here on eWn, it is believed that Steve Austin, The Undertaker, and John Cena will play a role in WWE WrestleMania 40 in some capacity.
According to a report from Pwinsider, there was an overture made to Austin for him to appear in some capacity over WrestleMania 40 weekend. However, the specific role has not been disclosed yet.
Furthermore, there have been discussions within WWE about including Hulk Hogan in some capacity during WrestleMania 40 week.