The DCEU had made a homerun when they made Wonder Woman back in 2017, so it would make sense that they would want to bank in on more superheroine-led movies. Now news has it that they're actually developing a Supergirl movie.
According to Deadline, 22 Jumpstreet and Shimmer Lake writer Oren Uziel has been hired to work on a script focused on Kara Zor-El a.k.a. Supergirl. In the comics, Kara was a member of Argo City, a city in Krypton which survived the planet's destruction. The city was then doomed to be destroyed as well, when Kara was sent over to Earth to be raised by her cousin Kal a.k.a. Superman.
The difference between both Supergirl and Superman (besides gender) is that Supergirl actually knows what it's like to be Kryptonian—as compared to Superman who only grew up on Earth. She does share the same powers though, but based on how Zod ‘gained' his powers in Man of Steel, I assume she would need a bit more training and discipline if she were to stay on Earth.
Seeing that Kara is one of the more obscure characters to the main audience, I would imagine that they would change her origin up a bit for the movie. With the Birds of Prey movie set to come out soon, I'm excited to see more superheroines get the attention they deserve.
Step-up your game, Marvel!
No release date has been set for Supergirl.