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Was it the same on other Japanese destroyers, or did they have single 13.2 guns?
Assuming that I understand your question correctly -
At the outset of the war, only the classes prior to the Fubukis carried any single 13.2mm guns, IIRC. The exception was the Type III Fubukis; they had two single 13mm guns mounted midships, on either side of the deckhouse, inbetween #2 funnel and the RDF/searchlight compartment.
During the war, there were undoubtedly many adhoc instances of DDs carrying single 7.7mm or 13.2mm guns. For instance, there is that well-known photo of Shirayuki at the Bismarck Sea with a 13mm atop a TT mount, surrounded by sandbags.
Shirayuki also shows that many of the Type Is were modified either immediately pre-war or early on to carry two twin 13mm mounts on a revised platform in front of #1 funnel.
Late in the war, destroyers across all classes could carry a mix of 13.2mm and 25mm single mounts.