If you haven't seen the movie yet, major spoilers follow.
Masters of the Universe includes three post-credits scenes, one of which features the live-action debut of She-Ra.
As Queen Marlena and Man-At-Arms discuss Adam's return to Eternia, Duncan ponders, "Perhaps one day she'll come back to us, too." We then cut to Adam's twin sister (assuming they stick with this aspect of the lore), She-Ra, wielding the Sword of Protection.
One of her allies approaches and asks, "Force Captain... Adora?," to which the statuesque warrior replies, "No... not anymore."
She-Ra is only shot from behind, and though she does turn her face to the side at one point (actress Lauren Saliu plays the role), the character will likely be recast if we do get a sequel. Adora appears to be standing in Etheria's Fright Zone in this scene, which means there's also a pretty good chance Hordak - who was Skeletor's even more ruthless mentor - and his Evil Horde will show up in the next movie.
While speaking to Total Film, director Travis Knight said he knows "exactly who" he'd cast as She-Ra if he did get the chance to helm a second movie, but doesn't want to jinx it by revealing the actress.
According to an updated synopsis, "In MASTERS OF THE UNIVERSE, Director Travis Knight brings the legendary franchise back to the big screen in this epic live-action adventure. After being separated for 15 years, the Sword of Power leads Prince Adam (Nicholas Galitzine) back to Eternia where he discovers his home shattered under the fiendish rule of Skeletor (Jared Leto). To save his family and his world, Adam must join forces with his closest allies, Teela (Camila Mendes) and Duncan/Man-At-Arms (Idris Elba), and embrace his true destiny as He-Man — the most powerful man in the universe."
Masters of the Universe stars Nicholas Galitzine as Prince Adam/He-Man, Camila Mendes as Teela, Jared Leto as Skeletor, Idris Elba as Man-At-Arms, Morena Baccarin as The Sorceress and James Purefoy and Charlotte Riley as Adam's parents, King Randor and Queen Marlena. Alison Brie will also feature as Skeletor's second-in-command, Evil-Lyn.
Sam C. Wilson will play Trap Jaw, with Kojo Attah as Tri-Klops, and Kristin Wiig recently joined the cast as the voice of Roboto.
Todd Black, Jason Blumenthal and Steve Tisch will produce, along with DeVon Franklin.