Point of Divergence ... Columbus when he arrived in the Bahamas had been searching for a passage that would take him to Japan. It is the reason why the term "Indians" has stuck for years, as Columbus had thought he had arrived in India due to the dark skin of the natives.
Meanwhile, in Japan, where Columbus was supposed to have arrived, Emperor Go-Tsuchimikado had ascended to the throne of Japan. At the time of Columbus' voyage, Japan had not been exposed to Europe, as there had been no official voyages there, and what little was known was mostly from rumors via the Asian territories that had managed to had a voyage to Japan. Also, Japan was just coming out of the Onin War, which signalled the start of Japan's Sengoku period, where individual daimyos warred for power and position in Japan.
Let's say somehow, by some miracle, Columbus managed to sail around South America and into the Pacific Ocean, and arrived in Japan lets say a year or two later, roughly 1493 - 1494. What would this contact with Japan in this era have entailed? Would Columbus have made a disaster of the expedition by trying to enslave the Japanese populace? Or would it have been a successful establishment of trade with the Western world?