Is there a evening shuttle bus around 22.00 from the airport to Plaza Hotel Beijing?

Yes, you can still take shuttle bus Line 1, get off at Shilihe Station. The ticket fare is CNY 24 per person. And the operating hours of this line are from 07:00 ~ 01:00 the next day. So you can catch it. After arriving, just walk south around 550 yards (500 meters) to find the destination.