According to unconfirmed research, the reason why Xiamen Xiamen uses "Amoi" as its brand is because Amoi is the Japanese name for Xiamen. "Amoi" is easily reminiscent of the Japanese pronunciation of Xiamen. In addition, the Japanese pronunciation of Xiamen essentially comes from the Portuguese "Amoy" for Xiamen. For this kind of thing, you can also think of Sina's name "Sina" (China).
You can query from Kingsoft PowerWord: Amoy n. Xiamen (a port city in Fujian Province, China). In Portuguese, Xiamen is AMOY and Macao is MAKAO.
In addition, through research, it is believed that AMOY comes from Fuzhou dialect: At that time, foreigners came to Xiamen. After landing, they asked a snack seller where this place was. The man said to him in Fuzhou dialect "Xiamen" ", the foreigner recorded it based on the pronunciation. The Japanese pronunciation follows the Fuzhou dialect name for Xiamen.