"How is the damage of karmic retribution quantified? As in how much damage would it cause, over a time t, to an opponent that has killed x people"
Depending on if you factor my timescale calculations, sans may or may not have enough power to completely annihilate the combined essence of a nigh-multiversial entity (Chara/Frisk fused) in almost 1/300,000th of a second... with KR, on a being that is detached and hateful, we're looking at a multiplicative factor of about 8x, through what is essentially soul poison, bearing in mind that the undertale SOUL is the culmination of your being, and therefore everything you are, all of your powers, etc.
"Is Blue mode basically just normal gravity manipulation/telekinesis in practice or does it have another notable effect?"
It literally alters the nature of the sum totality of his opponent, giving them the appearance of gravity of the soul.
The way I see it is this. It's the accelerator fight all over again. If she can accurately guage his abilities and move fast enough to DEAL with his onslaught then she can win, assuming she doesn't tank a blaster to the face, which she might, as those are instantaneous to beings that percieve light at moving equal to or slightly less than 10ft per second. Relying on data manipulation still requires her to be able to out-think the scenario. It really comes down to whether or not we accept my timescale calc from the enrico pucci fight. If we do, sans' ability to percieve at at least the level to which I've stated makes his chances much higher, since he can actually fight her on her level with attacks (Blasters) faster than she's used to, approaching MFTL. Accepting my timescale calc also accepts that his damage is absurd, with or without KR, due to there being 29507365998.3 'frames' per actual second. in the timescale I calculated, lowballing it.
