Can you generally say how much maneuvering space is needed?
Nope, there are theoretical turning circle calculations... otherwise you have to draw the cars to scale on the site plan (where the house is placed) and play around with the maneuvering a bit. That’s at least how I did it with us, rough estimate was enough and we have no traffic problems on our yard when it is used for guests, nor do we have to maneuver back and forth. But we also aren’t afraid to drive backwards. With a garage, that’s just how it is: whether perpendicular or parallel to the street...
Especially the length of the driveway would be interesting here.
The length is not relevant to your question. It depends on the area in front of it.
May I ask why you even come up with the idea?
Well, I don’t see any real advantage there. Crossing the "pedestrian traffic" to parked front door. It’s more pleasant when you can step out the front door without having to watch for traffic. If you have to build at least 5 meters from the street, 6 meters wide double garage, then you also have at least 2 parking spaces in front of the garage.
Marc+Jochen, it’s not that rare after all. And in my opinion it is even more practical because you use your own yard and it is structured by it. Attaching a garage to a house is common, but it usually means longer paths from garage to entrance door as well as boring/rectangular front yard/driveway.
Because of the direct access from the garage into the house, unfortunately there aren’t many possibilities for how the exit could be designed.
Well, you actually have quite a few possibilities. However, I wonder why the architect made such a drawing. You actually have other more common options. Driveway in the north towards east, garage in NE, trash corner behind it, entrance in the east, and counter the whole room orientation and let light shine into the house from the west.