Well, what is on my list to do for EV is sort of as you describe but not exactly.
I mean, it would not affect what happens when you press the brake pedal, but only what happens when you let off the accelerator pedal. There could be an off-pedal regeneration effect that is controlled by the paddles. I guess it would feel a bit like engine braking controlled by gears.
But as far as I understand, it's different from braking as it would not apply the actual brakes, and only applies a slowing effect on the drive wheels.