While we all know what Marvel films will be coming out in 2019, Captain Marvel, Avengers 4, and Spider-Man: Far From Home for those that don't keep track, the 2020 slate continues to be a mystery. Apparently, Guardians of the Galaxy Vol. 3 was meant to be one of the films slated for that year but then Marvel fired James Gunn and shot themselves in the foot.
Now that the third Guardians film is being put on hold, That Hashtag Show claims that we will be seeing these two films as part of Marvel's 2020 slate; Black Widow and The Eternals. Fans who have been keeping up with online news aren't too surprised by this but it would be cool seeing these two films come out on the same year, given how different they are from each other in terms of concept and tone.
A Black Widow movie seems to be more plausible the more news of it comes in, with Marvel supposedly settling on a few female actresses. While a lot of concrete news on the film hasn't been released, it does seem like it's becoming a reality. Most fans wanted a movie for her since Winter Soldier and Age of Ultron so this is a long time coming.
The Eternals is going to be one of the riskier projects coming from Marvel since it will essentially deal with deities. Some reports have claimed that the movie will be more in line with the Jack Kirby comics rather than the Neil Gaiman mini-series, with some emphasis on the origins of the Marvel Universe.
No official announcement has been made but this would be awesome if it happened.