Of course no, they used Ki-27 in Southern campaign, too.
Rather A5M is rare. Until the end of 1942 it was used by some second-line aircraft carriers and Japanese Mandate of South Sea islands. after 1942 they replaced by A6M and become trainer.
In other hand, Ki-27 is also retired during 1942, but different to A5M it was often used for offensive operations to support landing fleet and ground forces.
Afik, the Ki-27’s were only used offensively in the strategic resources area, china, the Philippines, over The Malay peninsula including Singapore, and in Burma, I don’t know of any that were used in the southwest Pacific area or New Guinea, as far as I know the first imperial Japanese army fighters to operate in the southwest Pacific area and over New Guinea used the Ki 43.
I understand, apparently “Pacific” what you think and what I think is different.
I thought it means the Pacific war campaign and you means more narrow meaning.
I hate mentioning someone who has nothing to do with the creation in any way.
So that’s it.