Why are all Japanese Ukiyo-e masters surnamed Gechuan? What's the connection?

Gechuan is equivalent to a pen name, belonging to a sect of Gechuan, which is the relationship between younger brother and grandparents.

When Gechuan Guofang was young, his name was Yoshito Saburo, and he studied under Gechuan Shiguo.

Kagawa Hiroshi, also known as Kazuo Ando, studied under Kagawa Kazuo.

Guo Xian, whose real name is Cang Qiao Xiong Ji, studied under the founder of Gechuan School, Gechuan Xiangchun.

Guo Xiang was very famous, and later his disciples inherited the same name, also called Guo Xiang. The first generation of Guo Xiang, the second generation of Guo Xiang, the third generation of Guo Xiang, and finally the sixth generation.