The Aichi M6A Seiran was not a well known Japanese airplane during WWII. It was produced in low numbers...only 28 were built. They weren't built as fighters but rather as dive/torpedo bombers.
Not land based, they were specifically designed, with folding wing and tail, to be carried aboard the huge I-400 class of submarine. Each submarine carried three of these planes.
If used successfully, they would have wreaked havoc. Their first mission was to blow up the locks in the Panama Canal, disrupting a major source of supply for the American forces attacking Japan. Then, while the submarines were underway (there were two of them), the orders were changed to attack the aircraft carriers and other ships at the American base at
Ulithi Atoll.
Fortunately, before reaching this target the war had ended, and the subs received radio reports that Japan had surrendered and they were to return to base.
Using a license built version of a Daimler V-12, they were equipped for rapid response by having heated oil and engine coolant pumped in just before the submarine would surface, so the plane could be catapulted quickly without waiting for an engine warm up.
At 400 feet long, these subs were the largest used by any navy during WWII and could easily reach the US coastline, as they had enough range to circle the planet 1 1/2 times.