Given that those monsters would be subject to the same world as we are and representing the same things, I think that there would be some similarities. Like creatures, most things evolve towards efficiency naturally. A map that used as media a circular surface (such a coconut) cannot be transported and stored with ease, and would be abandoned soon in favor of a flat, foldable map. Most arrangements would be inefficient both to convey information, carry and manufacture, so I think that a more-or-less familiar result would be achieved.
Of course, their different manipulation capabilities, access to material, cultural background, goals and reliance on senses would make sure that the map was diverse enough.

I think that this could be fun, and every entrant should start by stating the major cultural/physiological differences of their monsters. For example, if someone chooses wood goblins, their maps might not depict woods as trees and such, that is obvious to them, they would make special markings for those weird "treeless spots" that connect one "normal land" to another, or maybe focus on internal features of the forests that we would skip (the mushroom growing areas and whatnot). Or maybe a race that relies heavily on hearing could depict things by their sound, in a sort of a synesthetic way, I dont know

Could it also be a lite challenge, so the little kids can play?