Japanese superstitions in a Roman setting feels really out of place.
I don't think elemental spirits were a jp superstition? They had a more varied superstition with their "kami"s and "youkai"s iirc.
Can't actually remember where it supposedly originates from however, besides bland spiritual beliefs (I think the proper term is animism?) from everywhere in the world (but even then most of those are more varied and not truly connected to "elementals" of the "classical elements").
If anything, romans believing in it does make
some amount of sense actually, since it was somewhere around that area (greece?) that the idea of those 5 classical elements were invented, iirc (even if personifying it as spirits were not part of that, and if it is related then it is likely some later development when that philosophy encountered and mixed with animism).