More likely the translators, probably native English speakers, intentionally decided to use 'authentic', 'historical' Chinese names (as modern mandarn speakers would write them in pinyin) rather than the Japanese ones?
I agree that the effect could be really confusing though, and it's not what I would do!
(IIRC the fan translations of the Manga also gradually decided to change to use Chinese versions of the historical names, which I also found confusing - especially as they have kept some of the old Japanese names ones, so...it's a weird mix...)