I don't think they did in WW2. Every picture I've seen of a WW2 Fallschirmjager harness shows a single connectiont between their shoulder blades, they hung at about a 45 degree face down angle, with no control of the canopy.When did the Germans go to double riders?
The painter of that scene might have been a very realistic painter, but I doubt any paratrooper jumped with that much loose equipment on them. Can you imagine how many men would be injured trying to do a forward roll type parachute landing, with a folding bicycle behind them and a MG34, complete with a belt of ammo on their front.
The German paratroopers kept their MGs in containers dropped with them, not on their person.