Daniel, I also understand it. I changed the instrument language and saved it with “german” as default… ok for future projects.
But still it is like “not expected”, especially because everything in Dorico is so well structured and functional… eg a cue changes instantly when I change the voice … so one tends to expect, that the instrument lables changes instantly when you switch the language in the engrave options. If this was implemented, it could be useful to have a warning dialog that instrument labels changed “by hand” will be overwritten…