I need to add an autoharp part.
To the best of my knowledge, I think the answer is technically no if you mean it in the way that Sibelius does. But practically yes, if you just need a way to include that part in a score. I’m ready to learn otherwise…
Base on my limited knowledge I’d start with something workable in staff, clef and range. I’d then rename it, use an expression map for any transpositions needed. You can create brand new playback techniques if they are needed, and map them to any special autoharp articulations you might need. (Don’t know much about autoharp, but I imagine there are strums versus picking?) If I used it a lot I’d save it as a templete. The main thing I think you’d be missing is the coloring of any notes out of range that you can set in Sibelius, but since that doesn’t affect printing or playback - it would be minor to me. I made instruments in Sibelius mostly to set sound id’s, string tunings… what expression maps or alt tunings do in Dorico.
It depends what you want to do. If you just want a line of chord symbols, you might as well add a guitar instrument to the score and rename it as autoharp. On the other hand if you want to notate something like this …
I guess a “full implementation” would be something like the current harp pedal diagrams and out-of-range note detection, but on steroids
I had thought about using guitar but wasn’t sure if I could rename it. I’ll use slash rhythms.
Surely you can. What you can do is to use the instrument that’s closer to the characteristics and, most of all, notation, of your target instrument. Then you can just rename it.