Which upgrade from GH4? shooting less video now

I’d like to upgrade from my much loved GH4. It is a great hybrid camera but my needs have shifted to mostly still work that hasn’t been this camera’s strongest capability.

The GH6 would be my go-to but reviews say it’s not the best still photo choice.

Which lumix mft (love the light weight) is the best for still photos? G9 seems promising?

I could go full frame if the cost and weight work. Also must have a silent shutter capability (cant be clacking on sets or in meetings).

Thanks!