In its latest financial report, 2K Games, the owner of the rights to BioShock, Mafia, and Borderlands, confirmed that an all-new, yet unannounced project that has been in active development for quite some time now will be released by March 2020, making fans all around the world speculate what a new installment in one of the aforementioned franchises might be and when it will be finally shown.
Rumor has it that Hangar 13, the creators of the divisive Mafia 3, are co-developing an mysterious BioShock game alongside 2K Marin, the maker of BioShock 2's single-player mode. Considering that their last game, The Bureau: XCOM Declassified, was released around six years ago, there's a rather big chance the American publisher will finally unveil a BioShock: Infinite sequel in the near future.
The other obvious option is Gearbox's Borderlands 3, which has been teased for a long, long time now. Borderlands 3 had also leaked right before E3 2018 via a Walmart Canada placeholder, but it was one of those rare titles (like the long-rumored Splinter Cell) that weren't confirmed during the actual expo.
At the time of writing, 2K had not revealed any plans for next BioShock, Mafia or Borderlands games.