Currently there is no linkage to Chinese translation(s) of the Thera-gāthā & Therī-gāthā in SuttaCentral.
A quick search yields at least two translations.
 the Thera-gāthā & Therī-gāthā i 長老偈長老尼偈-正體pdf (download site)
This book was published in 2011 ;
The translator is [鄧殿臣 (1940-1996)] - short bio.
 Another version included on CBETA, translated by Bhikkhuni 雲庵
Download pdf site
This translator used rather archaic classic Chinese gatha style. Such a format most likely distorts the meaning due to the rigid stanza.
 There was a paper on the translations of these two works. It’s from Tsinghua University. Download pdf here.
I have not studied the paper but it might reference additional translations.