At this point in time, it is unclear as to what kind of changes Overwatch 2 could be bringing to the table, or if a sequel is even warranted. This is because Blizzard has been steadily expanding the roster of Overwatch over the past few years, and with it being primarily a competitive multiplayer game, it’s hard to imagine how different Overwatch 2 could be, especially amongst the competitive scene.
However, it has been suggested that some of the changes could introduce a new PvE mode, where players could get more of a backstory regarding the characters and the world in general. Take it with a grain of salt, but we should have more details in the coming weeks as BlizzCon 2019 is set to take place in early November.
Overwatch 2 is very much real and will be announced at Blizzcon after the short cinematic.
— Metro (@Metro_OW) October 18, 2019
In the meantime, it has also been reported that Diablo 4 could also be making an appearance at the event.