Both Panasonic G9 II and Panasonic GH7 have Four Thirds sized 25.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Another similarity between these two cameras is that both Panasonic GH7 and Panasonic G9 II sensors lack anti-alias (Low-Pass) filters. 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 G9 II and GH7 sensor size comparison.
Sensor Size and Resolution Comparison image of Panasonic G9 II and Panasonic GH7 Cameras
Panasonic G9 II and Panasonic GH7 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
Panasonic G9 II
or the
Panasonic GH7 ,
including hyperfocal distance.