Below you can see the front-view size comparison of the Olympus E-M1 II and Fujifilm X-H1. The Olympus E-M1 II is clearly the smaller of the two cameras. Its body is 6mm narrower, 6 mm shorter and 19 mm thinner than the Fujifilm X-H1.
The chart below depicts how two cameras compare with average dimensions of the cameras in their class.