Germany to honk kong via peking. Do you need visa for transit?

hi, i want to book a flight for honk kong (from germany) with a stop over in pekin. I have also read an artical about 72h free stand in pekin but did it apply also for honk kong?
and if yes can i stay 2 days in pekin for the germany->pekin->honk kong and another 2 days for the return fly from honk kong ->pekin->germany