Samurai Shodown has weapons, blood, and even fatalities. They just don’t go cartoonishly over the top.
Guilty Gear doesn’t have the same degree of bloody violence, but the production value that ASW brought could make the MK characters still have interesting finishers. Their work with Dragonball show that, if they wanted, they could also put in much care to make other peoples’ properties look right in an ASW title. Guilty Gear’s Instant Kill moves are functional fatalities as well, not just post match gloating.
With the above, the biggest isn’t isn’t the really the fatalities, it is just the clash of systems.
There are a number of older games, both arcade and console-only, that tried to ride the wave of Mortal Kombat’s blood, gore, and/or fatalities. Time Killers and Bloodstorm would not only fit right in with Mortal Kombat, putting the TK/BS characters into an MK engine would be an improvement for them. Primal Rage was MK with dinosaurs. While you’d think Liu Kang versus Vertigo would be a very short fight, the canceled Primal Rage 2 introduced the idea of human Avatars that could somehow also be large enough to fight dinosaurs. That could easily be worked into a mindless excuse for why the MK cast can do the same, and would probably still be a better excuse than MK vs DC used. Who’s waiting for MK vs Weaponlord? No one? Good. But it would be interest, though not necessarily fun, to see the MK characters rebuilt for Weaponlord’s engine.
Is it time for a giant Midway universe game? MK vs War Gods vs Bio F.R.E.A.K.S vs Mace: The Dark Age vs Rampage. It can go all King of Fighters and bring in fighting game versions of other non-fighting game properties… The Blitz Sports Team, The Total Carnage Warriors, …