In an interview with The Daily Star, Blizzard president J. Allen Brack hinted at the future of the Overwatch franchise. Similar to the Warcraft universe's three major titles, each of a distinct genre—Warcrafts I-III, World of Warcraft, and Hearthstone—future Overwatch games could potentially branch out into other genres as well.
The line of thinking that led The Daily Star to question Brack about the franchise's future in the first place was likely a response to the impending announcement of Overwatch 2. Recent leaks have all but confirmed a sequel or expansion to Overwatch that will include a PvE game mode, and possibly character progression that will introduce new abilities for existing heroes.
Should the Overwatch 2 leaks be accurate, then that makes Overwatch 2 something of a riff on the original Overwatch. The difference between the experiences of the base game and the upcoming sequel/expansion are more than likely going to be far less substantial than the differences between Warcraft III and World of Warcraft. So Brack's openness to other iterations of Overwatch is notable in that it would mean big changes for the franchise.
The Daily Star specifically mentions the possibility of mobile and VR games, with Brack in particular noting that VR gaming is at the very least on Blizzard's radar. This is very far from any sort of confirmation that Overwatch will end up on the App Store or a VR console at any point, but nonetheless presents the possibility that future iterations of Overwatch could come in forms that are unlike anything Blizzard has done previously.
Also looming large over Blizzard's future plans for its IP is Riot Games. Riot recently announced a first person shooter, collectible card game, fighting game and original anime series, all featuring its existing roster of characters in both League of Legends and Teamfight Tactics. Riot's CCG and FPS titles seem to be responses to Hearthstone and Overwatch, while the fighting game and anime are realms unexplored by Blizzard. Similarly, Blizzard's Heroes of the Storm likely exists due to the massive success of League of Legends. Both companies are constantly pushing one another, and Riot's unprecedented expansion of its IP could have lit a fire back at Blizzard Entertainment. In short: don't be surprised if Netflix announces an Overwatch anime in the next couple of years.
Source: The Daily Star