obtain a Chinese visa for Ethiopian Seafarers

Dear Sirs
Gd d
An Ethiopian seafarer Electrical Technical Officer is planed to join a newly construction vessel build in China / Jiangsu to supervise the various Electrical works for XY 104 newly build vessel.

Kell laying 24/02/23 - Launching 17/05/23 - final Delivery 31/08/23
Kindly advise what are the requirements to obtain a Chinese visa.
Your earliest reply would much appreciated it
Thanks in advance