There has been some interest on Facebook in a new program called Cantai, which allows the replay of vocals with the words in various languages, compatible with Sibelius, Dorico and Musescore.
I have signed up for it at the discounted pre-order rate.
If it's easy to work with, it seems to me this is a game-changer.
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Chris Crawley (composer and horn-player) using Dorico Pro 3.5.12, Sibelius 7.1.3, NotePerformer 4.2.0, Windows 10 64-bit, Intel Core i7, 3.30GHz, 64GB RAM, DacMagic 100