Must Japanese people's name be mapped to equivalent Chinese characters? According to this question titled "How do we choose the correct characters for a westerner name?", the accepted answer says the following:


  It's your name and you can arbitrarily pick characters to be your name.


Other answers also say that they can choose whatever they like, by its original meaning and/or its sound.

However, Japanese people already have names written in kanji. In fact I find that any name of Japanese people are simply mapped to its equivalent Chinese characters, and it seems to be that the sound never plays a role here.

Is it true that the name of Japanese people in Chinese must follow its Japanese kanji, or is it just a convention?

Also, if that is not the rule, is there anyone who breaks this convention, say among famous people in China?
Yes, if a Japanese name can be written in kanji, it is customary to read these kanji in its Chinese character pinyin, the Japanese pronunciation play no part.

The Japanese pronunciation of "田中" is "Tanaka",  But 田中 in Mandarin is read as / tian2 zhong1/ using Mandarin Pinyin and    /tin4 zung1/ in Cantonese using Cantonese Jyuping

If you are a Japanese named 田中 (Tanaka), your Chinese name should always be 田中 (tin4 zung1) also. Picking a different Chinese name, for example 田 (tin4) so your name can sound more Chinese, is considered insulting to your heritage.

Some Japanese first names do not have fixed corresponding Kanji, for example  あかね (Akane).  In this case, we have to choose among all the Kanji that is pronounced  あかね,  and 茜 is the most common one.