You certainly could publish these as a coloring book. One challenge would be orientation, as some images are landscape and some portrait. You'd have to resolve that. Otherwise, I suggest you take a look at other coloring books at Amazon to see what is the standard format and size and paper type.
I guess the other challenge would be volume. How many pages is typical for a coloring book? Would you have that many images? It must take a terrific amount of work to produce even one of these. They're quite fun and interesting! I bet you could get dozens of separate pages out of just one of these big pictures, if you could figure out how to extract or crop them. It would violate the integrity of the original. But hey, you could then offer the full images as a separate art book!
I guess the other challenge would be volume. How many pages is typical for a coloring book? Would you have that many images? It must take a terrific amount of work to produce even one of these. They're quite fun and interesting! I bet you could get dozens of separate pages out of just one of these big pictures, if you could figure out how to extract or crop them. It would violate the integrity of the original. But hey, you could then offer the full images as a separate art book!