Below you can see the front-view size comparison of the Fujifilm X-Pro2 and Panasonic GX85. The Panasonic GX85 is clearly the smaller of the two cameras. Its body is 19 mm narrower, 12 mm shorter and 12 mm thinner than the Fujifilm X-Pro2.
The chart below depicts how two cameras compare with average dimensions of the cameras in their class.