Wang Mang reformed the system and forcibly stipulated that adult men must have only one name and two characters. By the end of the Eastern Han Dynasty, this was basically the situation.
During the Three Kingdoms period, it was recorded that some people were named with two Chinese characters. Here are several situations:
The first is women: such as Zhang Chunhua, Wang Yuanji, and Sun Luban.
The second type is actually a Chinese character. Because compound surnames are rare, it gives people an illusion, such as Gao Tanglong, Cheng Gongying, Zhong Changtong, and Hu Muban.
The third type is translated names, such as Budugen, Shamoke, and Kebineng.
The fourth type is the exception of double names that are allowed: using words with blessings, such as the musician Zuo Yannian, Qin Yilu, the father of Qin Lang, and Tian Pengzu, the son of Tian Yu. There should be quite a few people who imitated the famous figures of the previous dynasty, Wei Wuji, Huo Qubing and Liu Bing.
The fifth type is that the recorder does not know the name of the person, but only knows his nickname, such as Liu Bei's uncle Liu Yuanqi and Cao Cao's counselor Xi Zhicai. This does not rule out the possibility of deliberately recording this way to avoid taboos. .
The sixth type is that the person's name is so famous that the world and even himself only call the person by name, no longer mention the person by name, and the history books do not record it. Such as Kong Ming's father-in-law Huang Chengyan. There were many such figures in the Southern Dynasties, the most famous being Gao Changgong, King of Lanling.
The seventh possibility is that he was born as a pariah and was unknown since he was a child. He only had nicknames, such as Yan Baihu and Zhang Feiyan.
The eighth type is fictional characters in literary works, such as Guan Yu’s defeated general Cheng Yuanzhi and Zhao Yun’s defeated general Xing Daorong.
Trivia: After Bai Qi, Lord Wu'an of the Qin State, died unjustly, his descendants escaped and changed their surname to Wu'an. In traditional opera, the weapons used by Bai Qi are chain and double hammers. Therefore, it’s hard to say whether Wu Anguo, the defeated general of Lu Bu’s army in front of the fictional Hulao Pass, is a double-named character.