Visa Application to attend Canton Fair 15th October 2023

My boss would like to attend the Canton Fair which is opening on the 15th of October 2023, he has an invitation for Canton Fair

1. He is a Russian Passport Holder, what are the requirements for an Express Visa?
2. Currently he is in Dubai and may you advise if he has to fly to Zimbabwe to apply for his visa or he can do it online?
3. How many days does it take to process the visa? Any possibility to have the visa in 1 or 2 days.