funny enough i’ve been doing just what you’re talking about the last 24 hours or so. what i did was taking the first pic (or whichever of them really) into photoshop an done a couple of duplicate layers. one layer i applied the cut out effect and then after posterize edges some contrast. i duplicated each layer all the time to keep an original and then just played with different methods. one thing that worked well was to, after applying above effects, deleting all the background color from one, so that it ultimately was left as a line drawing with alpha channel.
then import all your PS layers to ae and play with masking (union-skinning) off layers of the original image to reveal the new vison of the area beneath or the other way around obviously. if you have a couple of strong colours in either image you can key them out in ae and then mask them on layer by layer on top of a black and white line drawing. masking is basic, but if you animate masks on the right stuff with the right timing it can look great! don’t know if this is what you were looking for but hope it helps a bit, cheers/ d