Both Sony A6700 and Fujifilm X-Pro3 have APS-C sized 26.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
One other difference between these two cameras that is worth mentioning is that Fujifilm X-Pro3's sensor doesn't have an 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 A6700 and X-Pro3 sensor size comparison.
Sensor Size and Resolution Comparison image of Sony A6700 and Fujifilm X-Pro3 Cameras
Sony A6700 and Fujifilm X-Pro3 have the same sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture.
Sensor size sets the circle of confusion, so it drives how much depth of field each
of these bodies gives you at a given aperture. You can calculate it exactly for the
Sony A6700
or the
Fujifilm X-Pro3 ,
including hyperfocal distance.
