The The Mandalorian and a Rogue One prequel starring Diego Luna.
Obi-Wan is a character who's been extensively covered throughout various mediums of canon, appearing in feature films (obviously), animated TV shows, comics, and novels. Though Lucasfilm has explored parts of the Jedi's exile on Tatooine, that is the one period of Obi-Wan's life remaining to be depicted onscreen. Many fans presumed this Disney+ show would take place between Revenge of the Sith and A New Hope, and now Obi-Wan's place in the official Star Wars timeline has been confirmed.
A post on StarWars.com recapping the Star Wars reveals from D23's Disney+ showcase mentioned the Obi-Wan show is set "eight years after the events of Revenge of the Sith, where we last saw Obi-Wan delivering the infant Luke Skywalker to his Tatooine homestead." This means the series takes place 11 years before the Battle of Yavin and Luke Skywalker will be an 8-year old boy during its events.
Ever since Disney purchased Lucasfilm in 2012, there's been much fan interest in McGregor reprising Obi-Wan. His turns in the prequel trilogy are among the most acclaimed aspects of those films, and viewers wanted to see him come back in some capacity. That Lucasfilm took all this time to announce an Obi-Wan project speaks to their willingness to not move forward with anything until they were sure they had a story worth telling in place. It would be a shame if McGregor's highly-anticipated return was a letdown, especially since this has been a dream for many viewers. There's potential here for a different kind of Star Wars story, one that's a little more introspective and contemplative than the films. During his time on Tatooine, Obi-Wan was haunted by his failure and worked to overcome his grief, so that could make fore compelling character-driven drama. The possible small-scale nature of the story makes it an ideal venture for Disney+, rather than a blockbuster movie.
Production on Obi-Wan is slated to begin next year, so fans probably won't learn more about the show until 2020. It's possible it will be showcased The movies are going on a short break after The Rise of Skywalker, which means these TV shows are the immediate future of Star Wars. Lucasfilm has a lot invested in the Disney+ series, so hopefully Obi-Wan and the others do not disappoint when they premiere. If these shows prove to be hits, there's no telling what else the studio could do.
Source: StarWars.com