Trill of intervals other than a second

So I have been composing my nocturne and I have come to a part where I want a trill across a third. In particular A and C. And no, I am not wanting a double trill(the whole interval being trilled from A and C to Bb and D) because I have rarely seen such a thing and it is hard to do. Now, if I were writing this on pencil and paper, I could probably get away with using the trill symbol and writing a little staff to show that the trill is a third instead of a second.

But I don't think that is going to playback in musescore as a trill of a third, I think if I did that, I would just get a trill of a second interval from A to Bb.

Is there a way to get it to trill a third with the trill symbol or will I have to put 2 notes of half the length of the trill and then put a tremolo symbol between those 2 notes so that I get the trill to playback correctly?