I don’t know of any particularly good tutorials.
The basic way to do this is… pretty much fully create separate animations for the two characters assuming specific locations in the beginning and make it look good for that specific case.
For the duration of the animation you lock both characters in a static relation to each other and play both their animation for this event (player character → Finishing move, AI → Getting finished).
Interaction between dynamic elements is quite the pain in the ■■■ generally unless you hand over complete control to the physics system. With animations you can’t so you have to completely animate all individual interactions you want and play the correct one when appropriate… plus you pretty much always also move the characters around a little bit beforehand to make them snap exactly in the location the animation has assumed.
Before playing the finisher animation itself you leave a little time to interpolate / transition between a middle pose before you hit the first keyframe of your finisher to make it look decent. And voila. You’re done.
It’s a whole lot of content / animations needed to look good and even more work in engine to feel smooth which is why you see this type of gameplay mostly in big budget productions.
There sometimes is some physics support / more dynamic stuff going on but that is quite very advanced technical art stuff.
