Condensing of piano staff

Can a piano staff be condensed into one line?
I want to write separate notes for secondo or primo with condensed staff from the other player.
I couldn’t get it with dorico.

By the way, condensed lines (e.g. for violins) cannot be scaled (staff size).

No, Dorico does not support condensing the two staves of a single instrument into one staff.

Too bad, but thank you for the quick answer.
I have to take violins to create only PDF and do without playback.

How can I scale condensed lines (e.g. for violins)? Staff size scaling doesn’t work

You could try “cues”. I haven’t looked to see if you can expand the note sizes in cues, but it’s a way to overlay the two pianos on one stave.

Yes, cues is also a solution if there is no overlap.
But in the main stuff you have to correct a lot by hand, e.g. stem direction.