The original mid-air refueling tests were done with a single-engined propeller fighter. You just have to have a system that refuels through a receptacle on the top of the plane- probably behind the canopy.Like those big whirling propellers on the front end of the aircraft. No single engine WW2 fighter would be able to refuel using either the probe and drouge or the flying boom system because of this. Modern jet fighters generally have their engines below or inside the fuselage to facilitate their refueling.
If you take a look at this picture, the refuelling receptacle on the F-16 (bottom aircraft) seems to be behind the canopy. A single-prop aircraft could refuel like that without much trouble. I don't know if the Tucano- the only single-prop combat aircraft still in production AFAIK- can refuel in mid-air, but it certainly looks possible with a flying boom. Probe-and-drogue is out, though.