As a Japanese person (apparently)... you should know that the phrase "Chinaman" (支那人 is a racist slur.
Since of course, it is you guys that use it the most. I believe you pronounce it as "Shinajin".
Really is it so,unaware about that
P.S-Do u know that in game Cricket their is a particular bowling style called Chinaman,and do u know what is the irony,so far we dont have any Chinese bowler who use this style