The issue is reported before, in a not that clear way:

https://forums.zotero.org/discussion/101281/help-please/p1

All the following styles need improvement:

https://www.zotero.org/styles?q=gb7714

Currently even for English citation, Chinese characters involve in:

https://i.stack.imgur.com/F4CK0.png

It's clearly against the standards. According to the standards, when citing English publications, English should be used. ("等" should be "et al.", "第2版" should be "2nd ed", "见" should be "in", and so on. )

FYI, here is the GB/T 7714-87:

https://github.com/saccohuo/GBT-Standard/blob/master/GB 7714-87 文后参考文献著录规则.pdf

Here is the GB/T 7714-2015:

http://journal.ustc.edu.cn/uploadfile/yjsjy/20161108/GB T 7714-2015信息与文献-参考文献著录规则.pdf