NetherRealm are reportedly looking into crossplay possibilities for Mortal Kombat 11, but if it happens, the feature will come at some point after launch. The leading factor in crossplay potential is the game's engine - Unreal Engine 4.
Crossplay has become one of video game features that keep grabbing attention whenever they are mentioned, in no small part thanks to Epic Games and their crossplay initiative that spanned over the course of 2018. Fortnite became the first game that had crossplay between PS4 and other consoles, but Epic are not stopping there as they have announced a plethora of for games running on Unreal Engine.
Thankfully for Mortal Kombat 11, NetherRealm have migrated from Unreal Engine 3 to Unreal Engine 4 which will power the latest blood and gore fest. Questions about crossplay support were inevitable, especially because the game will release on four major platforms - PC, PlayStation 4, Xbox One and Nintendo Switch.
According to a from Wccftech, Mortal Kombat 11 game designer Derek Kirtzic stated that NetherRealm can't explicitly talk about the feature at the moment, but it is definitely a feature they are looking into and hoping to bring to players at some point.
This is not an absolute confirmation, but considering that Mortal Kombat 11 will be available to so many players across four different platforms and that Epic Games are going to release the aforementioned features that would ease the development for crossplay features, it would be a huge waste of an opportunity for NetherRealm if they decided to skip crossplay.
On top of that, Mortal Kombat's genre puts it into a specific position where no platform would be at a disadvantage due to input methods, other than Switch in some rare cases.
For example, shooter games are facing issues from console gamers who are pitted against PC players who have more precise means of control input via keyboard and mouse, while PC players take issue when aim assist is enabled for console players who play in the same game.
Due to the nature of fighting games, the optimal input are gamepads for the most part, and many PC users already have gamepads, which will mean all platforms get to play with the same input. The rare cases we mentioned before are the arcade stick controllers which can be found on PC, PS4 and Xbox One, but these devices are rarely used except outside of the elite competitive player base.