Create a ground plan of 50% copper

I expect to create capacitive touches on a PCB. To avoid issue with other components on the opposite side of capacitive touches, some books argue that a ground plane shall be add between the two faces, but to avoid a the bad capacitive effect of this ground plane on the capacitive zones, it is better to create a ground plane between 50 to 75% of coper. I’ve only find a way to create a 100% coper ground plane. Is it possible to do this ? Would it be a further improvement ?

I think you’re talking about a hatched fill. Right now, that would be a feature request for improvement, but if I needed a hatched fill, I’d write a python script to draw a bunch of criss-crossed traces or lines on the needed layer.

It would be better to use a hatched fill. If it is possible to have a hatched fill x filled ground zone, it would be great !