Add octave-displaced alto clefs for C-centred piano notation

[philbennetts]

I’m a piano teacher and composer developing a C-centred notation system for piano, described here: Zenodo paper.
Could MuseScore add four functional octave-displaced alto (C) clefs to the Clefs palette: +8 and +15 (one and two octaves up) and −8 and −15 (one and two octaves down)? I’d like the clefs to control both note interpretation and playback.
At present, I have to add octave indications as expression text by hand. These are attached to notes, may need repositioning when the layout changes, and don’t affect playback. Having these clefs available would make it much easier to write and test the system in MuseScore. Thanks!