Needs a thin adapter
Sony E and Canon EF-M sit at exactly the same distance from the sensor (18.00mm), so focus is preserved by a flush adapter that adds no length — a thin ring rather than a tube. These pairings usually have cheap, widely available adapters.
Coverage & framing. The lens covers more than the sensor needs, so the body crops into the frame — roughly 1.6×. A 50mm frames like a 80mm would on Full frame.