I wish Scrivener would allow me to set which language I’m writing in, without forcing me to change the system language.
I have my system language in my native language (obviously), but some of the things I write in Scrivener are in English. It seems to detect the language for spell-checking alright, but things like chapter headings or typographic quotes follow my native/system language, not the document language.
My search indicates that there’s no such option, so I’ll consider this a feature request.
Yes, as far as I am aware the systems you are referring to, like the localisation of the word ‘chapter’, as well as the OS’s plain-language counters for ‘twenty-three’ being translated, are all not things that can be flipped around on the fly like that, or selected individually.
So it has always been a limitation that one must set their region accordingly to what they are compiling, and then set it back once done. At least Apple does make this relatively easy to do.
Typography on the other hand is a separate switch, when you can find by searching for ‘smart quotes’ (or equivalent in your native language) in the Settings tool. That is also where you can set the master switch for spelling and grammar, but note Scrivener itself can be switched independently, which is probably more what you want if the automatic detection needs some help. See Figure 15.1 in the user manual for the panel where that is set, and how to get there.