During (and before) WWII, the Imperial Japanese expressed an interest in German aircraft designs and Heinkel even provided an engineer who assisted the Japanese with several designs. The Germans on the otherhand, expressed little interest in Japanese types.
However, a little known fact is that the Germans operated a Nakajima E8N aircraft from their Auxiliary Cruiser, the DK Orion (HSK-1), making it perhaps the only Japanese military aircraft operated by Germany during the war.
The Orion put to sea in April 1940 and had a single scouting aircraft at the time, an Arado Ar196. After a successful deployment in the Indian Ocean and South Pacific, the Nakajima was aquired by the German Naval Attaché to Japan, Vice Admiral Wenneker. The new E8N was transported out to the Orion by the supply ship Münsterlamd, which met the Orion near the Marianas on 1 February 1941.
Not much more is known about the E8N's service or it's fate. The Orion continued to be successful in it's tours, eventually being retired as a raider and becoming a training ship in 1944. In 1945, the Orion was pressed into service to evacuate refugees from the Baltic and was attacked by Soviet bombers of the 51st mine-torpedo Aviation Regiment and set ablaze. The crew was able to ground the Orion near Sweinemunde, losing only 150 persons out of well over 4,000.
It's also interesting that the German E8N was finished in British markings, too (seen in the attached photo).