The name Wanshū (腕秀) in Mandarin means "Excellent Wrist" and refers to a typical technique of this form.
[1][2] A poet, calligrapher, diplomat, and martial artist in the Shaolin tradition of Fujian White Crane, he is often credited with teaching chu'an fa to the gentry of Tomari.
Regardless, many karate traditions include a kata bearing the name of Wanshū or a variant (Ansu, Anshu) which vary in schematics but carry certain distinctive similarities.
The two main versions are Matsumura-Wanshū and Itosu-Wanshū, Itosu most likely having learned it from his teacher, Gusukuma of Tomari.
Wanshū, while still bearing this name in certain karate styles, was renamed Empi by Gichin Funakoshi for use in Shotokan.