Some of you guys out there asking a lot of questions these days seem to be in sore lack of a researcher’s attitude, patience and also - sorry to say so - the willingness to think by themselves.
The very scenario you’re using as an example here provides a lot of answers on why it cannot work, if you care to use your brain that is. Because a person receiving a punch will not react on it like a mindless softbody without a neural system, instead its reaction will be a mixture of passive, physics-driven movement and counter-acting driven by her neural system to avoid falling down (at least if she’s not out cold immediately). How the heck should any Blender physics sim achieve that? It is obvious that this would require a different class of simulation tools, more like an AI with knowledge of human anatomy and biomechanics, something like Boston Dynamics uses to make their robots walk and do backflips.
A bit more of thinking would tell you that it is very difficult if not impossible to “just” take care of the passive, pure physics part and keyframe the active side, because that would mean feeding back the simulation result to the very armature driving it, which obviously would lead to a dependency loop. You probably could try to struggle with the pair of armatures you’d be bound to use for such a character, and keyframe both of them … which would be nasty to manage, you’d be better off keyframing all of it in the first place.
Oh, that’s really bad. Professionals do it in about an hour, so maybe you should just give up.
Jokes aside: better get used to the idea that setting up an advanced rig for a character can keep you occupied for a while … hint: weeks. Concerning your personal progress: learn to think in years, not in days. And don’t expect others who got used to that kind of timeframe, aquired the patience and still are dealing with their frustrations on a daily base … don’t expect those others to be overly patient with your laments here.
@NiklasWerth probably used dynamic paint waves to set that up quickly, and indeed it shouldn’t take more than adding a canvas to the head, a brush to the sphere and setting up the canvas as “Waves”.
Except all that: please learn to be accurate about terminology, because it matters when discussing complicated topics like this one. There is no ‘action modifier’ in Blender.