Type of document
Among the authorities recognized
for certifying Chinese documents,
there is:

Studies, training and internships
Document issuer
Notary of the country
issuing the document

Notes:

A copy certified as true by the document issuer is always the preferred format. Note that processing time is required to verify the accuracy of the information you have provided. The processing time could be shorter if you submit copies certified as true by the issuer.

意思就是由学校直接出具英文成绩单毕业证是最快的，不然的话就是公证翻译件(含原件复印件)。