How long does the consular processing take?

My wife has an H1B visa and lives in Pennsylvania, USA. I have an H4 visa, but still live in Germany. Her employer would like to sponsor her an EB3-Greencard. The PERM-Process will (hopefully) be approved shortly and the immigration lawyer involved is preparing the I-140 right now. Originally it was planned that I enter the country before the I140 is applied for and we then file an H4-EAD.
Due to the current developments in the US labour market by Covid-19 (=26 million new unemployed people), we now want to do the consular processing for me.

My questions: When my wife has received her green card, how long will the consular processing procedure take? And: do I have to submit any documents for me already in the I140 process (for my wife)

Is your priority date current for your country ? What is your country of birth for Green Card.
Also, currently there is a 60 days ban on the issuance of Immigrant Visas too due to proclamation. Check this.

Is your priority date current for your country ?

Yes.

What is your country of birth for Green Card.

We are both German citizens, were also born in Germany.

Current status (June 21, 2020):
PERM was approved and on May 4, 2020 the I140 was received by the USCIS (but without premium processing). So the 60-day ban is irrelevant for our case at the moment, because the processing would not be finished in these 60 days anyway.

Just out of interest: When my wife has received her greencard (i.e. after the I140 + I485) my consular processing can start, right ? Or can you start it while her I485 is still running ? What steps have to be taken to perform the consular processing ? I130+I485 ? How long do we have to count on ?