Likewise, I’ve been working on a project for a few years which would utilize a number of screens for playback, but haven’t settled on how to edit the material. As others have suggested, I think figuring out the display tech may be the place to start. One solution I’ve seen was an art project that used nine screens all in sync, each stream recorded in a different room in one house. They were using Brightsign servers. I’ve not gone down this rabbit hole yet, but it looks like they have software to create streams which are served by their display boxes, sent to screens of any type.
I’ll be very interested to hear what others suggest for your project. Mine is much less complicated than yours, as I envision only four screens running simultaneously, with some material sliding from one screen to another.