if you watch HBO VICE and admire the multi image open motion effects you'll immediately appreciate my question and perhaps know the answer. What effect package do they use?
During the days of Linear and with triple re-entry switchers, ADO and GVG MkII DVE and D-2 Pre-Read I created similar effects for videos. Now I edit on PPRo working on multCam projects and would like to create simulor effects.
You can do something like this in After Effects. With some pre-comping it could be relatively flexible. Motion-graphics-wise, I would call this sequence 'not too complicated' — it's more about the technical work of getting all the shots across correctly. Of course, Vice did a cool job of coming up with it: nice one Vice!
I would probably make a test case, then make a simple timing 'mock-up' in Premiere for use on the timeline that allows an editor to make shot selections based on content, then import the final selected shots into AE for adding into the pre-comp system. Not too elegant, but Essential Graphics is far from ready for this sort of thing. ☺
I've not used Apple Motion seriously in years, but it might also work well. Any Motion-ninjas out there...?