Both Olympus E-M5 and Olympus E-M10 III have Four Thirds sized 16.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Below you can see the E-M5 and E-M10 III sensor size comparison.
Sensor Size and Resolution Comparison image of Olympus E-M5 and Olympus E-M10 III Cameras
Olympus E-M5 and Olympus E-M10 III 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.
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
Olympus E-M5
or the
Olympus E-M10 III ,
including hyperfocal distance.
