I guess that crossbows are odd dwarvish weapons in Central Genertela,
may or may not be available in the Far East (dependent on how technological
you view the Kralori to be) and either fully embraced or despised in the
West. I would suggest they are common in Ralios, as a melting pot of
culture.
For a central Genertelan campaign I would make them extremely odd and
dwarvish.
I would also suggest that the Pelorians have no real interest in
mechanical technology as opposed to magical technology, and as such
do not use them.