I still hope this above is possible. However…
… if that is not possible to do with webflow, I would alternatively do something like this: Image 2018-09-21 at 9.52.01 PM
But I cannot figure this thing out either - when you click on arrow and one new element scrolls into view from right. I could use a slider, but then it would slide all four altogether and I probably wouldn’t be able to put mp4 on each tile hover (see OP).
Thanks!