I'm new to editing, photos and videos, have PS and AE, and I'm very well versed in computers/devices and most any software/hardware and can pick most things up very quickly, but for editing, it may as well be Mandarin.

Goal (yes, it's corny...moving on) https://www.youtube.com/watch?v=L5hD3i9HXxw

Basically, in an effort to not waste anyone else's time, if someone could just tell me what this effect or type of video is actually called, perhaps an actual name of the concept will enable me to quickly search again on here or google/youtube with better results in finding a tutorial on how to make one of these. I kept calling it things like "head swap meme video clips/change head meme videos..." thought I had a breakthrough with seeing them called "big head...", and then "bobblehead effect"...no doesn't appear that is correct, and no real help finding help using those terms.

If someone could let me know a more popular name for this editing concept, or point me to some tutorials, video or written up on here, maybe any suggestions or shortcuts they use, that'd be sweet. For example, I am cropping the faces using PS, and the pen tool, which is quite tedious (not to mention I am assuming a .psd or .jpeg file is what will be used in AE to add them in) so if anyone knows of a plugin or any method of quick face detection and cropping/copying the head to be saved and used on its own, that'd be a time saver and appreciated!

Summary What is this type of video/effect called? Any tutorials on how to do it easily? Any advice on plugins, effective ways of facial detection for cropping a head to use? Any other tips or pointers?

TY