Well, the difference between this and the ones I've seen is that all I have ever seen spray the fluid up and coat from the bottom, not the top.
I suspect that a top fed coater would have an issue that as the feed hopper fill height varied then the coating thickness would vary. But maybe not, or at least maybe not within a close enough range.
I do think you could modify this thing to keep it continuously fed with coating material, but you would have to have some way to dry the coating before rolling it up. That's going to take a bit of floor space in a dark area. And with no way to inspect your product before slitting your emulsion defects will be pretty hit or miss.
But what the hell, some film is better than no film, right?
Don't these kinds of machines use rollers to get the coating thickness desired, then used a sized blade to cut the coating from the roller and drop it onto the film/paper/whatever?
I had a PDF of a really old book that had some detailed drawings of glass plate coating machines that worked like that.