Keanu Reeves has addressed the question which apparently Mortal Kombat fans have been asking. In an interview with Esquire to promote The Matrix 4 (thanks, Eurogamer) the internet's favourite nice guy was asked about whether Neo or John Wick would appear in a Mortal Kombat game, if it were up to him.
“If it was up to me? No,” says Reeves, though rather than going straight for the Fatality he then offers Friendship. “Mortal Kombat is awesome in so many ways, but I think… um you know, Neo, John Wick, yeah man they're doing their own thing. Mortal Kombat's doing their own thing.”
I like how he says “awesome in so many ways.” You could interpret that in so many ways.
It's probably worth saying that the rights to the Neo character rest with Warner Bros., which publish Mortal Kombat, so this crossover remains a genuine possibility. The John Wick franchise is controlled by Lionsgate.
Reeves' comment puts paid to the hopes of Mortal Kombat fans who wanted to be The One. This was mainly folk wanting those characters in particular (Mortal Kombat 11 has featured classic action heroes like The Terminator, RoboCop, and Rambo) and series co-creator Ed Boon occasionally teasing the possibilities.
Boon, currently Mortal Kombat developer NetherRealm's creative director, has in the past has talked about adding Neo and John Wick to the series. He also said at one point that Neo was suggested for Mortal Kombat 9, but they weren't sure of the fit: “I remember [Warner Bros.] brought up Neo. So there were a whole bunch of ones that for business reasons or that creatively we didn’t think they’d fit,” Boon told Game Informer. Whatever the fans think, Boon is probably right: certain characters can fit in amongst the blood and viscera of Mortal Kombat, but seeing Neo rip someone's spine out just doesn't quite fit that character's vibe.
Reeves and his characters are found widely elsewhere in video games of course, the most notable recent example being his turn as Johnny Silverhand in Cyberpunk 2077. There's the official and very decent John Wick Hex, and a big handful of Matrix games: including the beat-em-up Path of Neo, which saw you raise hell through a re-working of the movie storyline before fighting a city-sized Agent Smith.