HQ5x4 is the standard pusher prop, this prop is supposed to rotate counter clockwise if looking down from the top. So this prop should go on the rear left and the top right.
R stands for reverse, which means that the prop spins clockwise looking down from above.
So the 5x4x3 R should go on the rear right and the front left.
Keep in mind that this configuration would only be true for quads running cleanflight, baseflight, or Betaflight.