Below you can see the front view size comparison of Sony A7 III and Leica X2. Leica X2 is clearly the smaller of the two cameras. Its body is 3mm narrower, 27mm shorter and 22mm thinner than Sony A7 III.
Sony A7 III vs Leica X2 - Front View
Sony A7 III vs Leica X2 - Top View
The chart below depicts how two cameras compare with average dimensions of the cameras in their class.
Camera Size Comparison
Select Two Cameras for Size Comparison