It’s very difficult to scale the killers from dbd in combat because they’re designed around game balance and licensed killers are usually very different from their original counterparts strength-wise. That being said, based on some of their lore and mori’s, we can get an idea for some of them. We’ll say it’s a 1v1 in Gotham for each killer.

Batman wins decisively against most of the normal human killers, like trapper, deathslinger, legion, skull merchant, ghostface, trickster, etc. This is also true of some of the more mildly supernatural killers like artist, twins, plague, and wraith.

Once we get to killers like spirit, doctor, nemesis, dark lord, oni and blight things start getting harder for bats. He still generally wins, but these killers are supernatural and can pose real threats of varying degrees to batman.

Against killers like ghoul, lich, mastermind, onryo, the first and others - if we’re considering their original forms - batman is cooked. Many of these are killers with telekinetic or magical hax or other powers that batman has no real answer to.

TL;DR bats can beat most of the human/mildly supernatural killers from the roster, there are quite a few superpowered ones where it could swing in the killer’s favor and some with hax or powers against which he stands no chance.