Director Scott Derrickson has openly hoped to do a sequel to his 2016 Marvel Studios film Doctor Strange, but that's not the only thing he hopes is in the Marvel Cinematic Universe's future. In an interview with Screen Rant, the director was asked about new characters that could be brought into the MCU and name-checked the Fantastic Four as the one he wants to see most.
"I mean, there’s a lot of discussion about Moon Knight maybe coming into the MCU. I think that’s a good idea. I dunno… Actually, scratch that answer. Here’s my answer. My answer is this: I still have hope that Fantastic Four can be properly brought into the MCU because a lot of Doctor Strange – that’s the comment I read the most during that," said Derrickson. "I love those characters and I think that they still deserve another shot at finding a true home in the MCU. I still have hope for that. That’s my honest answer.”
20th Century Fox has held the Fantastic Four film rights since the mid-1990s, producing three films so far, ending with a poorly-released 2015 reboot. Marvel has reclaimed film rights to properties before, including Iron Man and Daredevil, and has also worked out unique deals such as with Sony/Spider-Man and 20th Century Fox/Ego the Living Planet.
So, while rare, the Fantastic Four appearing in the Marvel Cinematic Universe remains a possibility.