There doesn’t seem to be any way to transpose by key in Dorico, but only by interval. And there doesn’t seem to be any way to respell notes and chords in a whole flow. Am I missing something? Or do I have to export my flow, transpose it in Sibelius, then import it back?
(I found a trick: I transposed down a minor second from Eb to D, then up a major second from D to E. But this is something that you folk should fix.)