This looks like it will be easier to build than design B

It would appear, at first glance, that applying rotation would not change the resultant vertical component (pitch), if the curve is designed properly. The horizontal (yaw) force will come by increasing the horizontal force on one side while reducing it on the other. The optimal design would probably be such that the downward force on each sides of the XZ-plane are balanced for any position of the stabilator. Also, the optimal design would probably be such that the rotational force about the X-axis is in balance for any position of the stabilator.

Theoretically, it looks like this arrangement could be designed so that when pedal is applied there will be yaw but absolutely no pitch and no roll. Also the yaw force will be greatest at hover and least in forward flight, which is good.

If the blade were to be given a slight positive pitch then in forward flight it would give the helicopter more negative pitch and assist yaw more; if this was ???

This airfoil should have an adjustable pitch of about 30 degrees, in the negative direction for autorotation. In a vertical descent autorotation with no horizontal movement the yaw control will be reversed, since the wind will be against the lower surface of the airfoil. This wind will also impate a forward thrust to the helicopter.

This method may not give enough yaw in forward flight in a strong cross-wind because the rudder will resist the applied yaw.