It's been over a year since NetherRealm Studios announced the completion of post-launch development for Mortal Kombat 11.
Unless Boon somehow has something else in mind, these abbreviations are clearly pointing towards either Injustice 3 or Mortal Kombat 12.
The "pattern" that Ed Boon is referring to is a reference to how NetherRealm Studios tends to alternate between titles in the Mortal Kombat and Injustice series since Mortal Kombat 9.
During that same Q&A session, Ed Boon also stated that NetherRealm Studios "will soon fix" the issue regarding the scarceness of 3D era characters from modern Mortal Kombat titles.
While we can certain expect plenty of horror movie characters in NetherRealm Studios' future Mortal Kombat games, Ed Boon is adamant that Freddy Fazbear from the Five Nights at Freddy's series will not be among the guest characters.