AI offers this, with no guarantee that it is 100% accurate...
"No, Crescendo does not support placing the octave indicator (8va) directly above the treble clef as part of the clef symbol itself, like in your found example. Instead, the software places it below by default when selected.
Octave Notation Method
Use the dedicated Octave line tools from the right-side toolbox to add 8va or 8vb markings. Click to set a start point on the staff, then an end point to span the desired notes or measures—these attach independently and move with the music. This standard approach reduces ledger lines for high soprano recorder parts without altering the core clef symbol.
Clef Change Options
Right-click the existing treble clef, select Clef from the menu, and choose alternatives like alto or tenor, but no built-in octave-modified treble (e.g., soprano-specific) appears in documentation. For descant/soprano recorder in C, this octave marking convention matches common practice.
Workarounds
Transpose notes up an octave via Score > Transpose (limited by staff range; switch clefs first if needed) to keep pitches in standard treble range without extras. Or combine with octave lines for clarity—these play back correctly in MIDI. Check NCH tutorials or support for updates, as features evolve."