These easiest way to do it is to add a Transposition to the Full Score, using the Clef and Transposition Override function in Setup mode.
Right-click on the Full Score Layout item in the right-hand panel in Setup mode.
This will ensure that the Parts are unaffected, so that Piccolo and Double Bass humans won’t be confused by seeing the Wrong Thing™.
Here’s a project that has what you want.
Octaves.dorico (895.7 KB)
The Piccolo is playing notes an octave above the Flute; and the Contrabass is playing an octave below the Cello. (Because that’s what they’re for and why they exist.) Here, the full score shows them at different staff pitches from their cousins; contrary to normal practice.
Really, I’d just try to accept that Piccolos are “flutes that play an octave higher”; and Basses are just “Cellos that play an octave lower”.