Both Sony RX1R and Leica Q-P have 24.0 MP resolution sensors but Sony RX1R's sensor is Full frame (35.8 x 23.9 mm ) and Leica Q-P's sensor is Full frame (36 x 24 mm ).
Since Leica Q-P's has a larger sensor area with the same resolution, this means that it also has a larger pixel area hence better light collecting capacity for a given aperture compared to Sony RX1R.
Another difference between these two cameras is that Sony RX1R's sensor lacks anti-alias (Low-Pass) filter. Removing anti-alias filter increases the sharpness and level of detail but at the same time, it increases the chance of moiré occurring in certain scenes.
Below you can see the RX1R and Q-P sensor size comparison.
Sony RX1R and Leica Q-P have almost the same sensor size, so neither of them has any significant advantage over the other in terms of providing control over depth of field when used with the same focal length and aperture.