Thanks. I tried it, but...
The game's default language is Italian. It has an English translation. Being English, it's only viable for me to work with the English texts and voice scripts.
I can only auto number the lines to the default language (Italian).
Although it also numbers the lines of the English translation, it no longer displays
any English, whether I select to view default or English translation, and so exporting the voice scripts always occurs in Italian.
From that point, attempting to switch to English nothing happens, it just remains all in Italian, as if it's overwritten the English or something.
So I'm back at square one

I don't want to set the translation (English) as the game default because that will overwrite and destroy the Italian text.
If there is no way around it, I guess that's the only option, turn it into an English only game.