When did Xu Fudong cross Japan? Is it legend or historical fact?

Xu Fudong's trip to Japan is a historical fact, but it should not be true. After all, maybe Japan was just an island at that time, and whether there was anyone on it was still a mystery. Although Japan does not admit that Xu Fu has been to their territory, there are statues and cemeteries of Xu Fu in Japan.

Xu Fu is a famous alchemist in Qin Dynasty, that is, a person who specializes in alchemy. According to historical records, Qin Shihuang was a king who pursued immortality. His lifelong pursuit is immortality, so he sent many people overseas to look for elixir of life, and Xu Fu was one of them. In fact, it is ridiculous to seek immortality overseas, but because of the technological level at that time, many people still believe it. Wei Fulin * * * stayed in the East for three times and came back after the first time, but after he came back, Wei Fulin was afraid that Qin Shihuang would punish him, saying that overseas immortals thought he didn't bring a gift, so they didn't give him an elixir. Upon hearing this, Qin Shihuang immediately asked him to take 300 virgins, countless treasures and grain seeds and set off again.

This time, Xu Fu didn't come back until nine years later. Then Xu Fu told Qin Shihuang that he couldn't kill the dragon because he met it, so he came back and asked Qin Shihuang to give him some archers to shoot the dragon. Qin Shihuang also believed him. Later, he was given an archer, and finally the archer killed the dragon. Qin Shihuang thought he would find the elixir of life, so he sent Xu Fu to find it, but in the same year, Qin Shihuang died of old age. After learning the news, Chuifu decided not to go back, so Chuifu lived on the island with 300 virgins.

Many people say that the place Xu Fudong crossed was Japan, or maybe Xu Fujian made Japan, but because there is no historical data to support this, I can only guess at random.