Let's say character A can make people faint with a sligh tap at an extremely precise pressure point on the side of their heads. Character B has high-mid regen. Character A tries to apply this technique in character B. He proceeds to make character B faint, without actually damaging him, or is it plain useless?
This really depends, if its a user such as Kenshiro, then they will be stuck in an endless loop. Kenshiro blowing character B to pieces then character B comes back with the regen. If its a Byakugan user then character B will faint from being starved of energy or chakra. However this doesn't mean Hakuto useres can beat Character B with pressure points that induce sleep or forced movement. Essesntially saying that Character B is still defeatable but it will have to be by other methods then brunt force.
It would depend on how the pressure point is explained in verse. If it's something like causing your neurons to malfunction, it would be fixed since mid regen can deal with the destruction of the nervous system. If it's something like messing with Qi flow, then it probably wouldn't be impacted by the regen.