When trying to export XLIFF for my development language there is no way to include translations.
I have a development language set to Czech like this
When I want to export existing translations for Czech - there is no checkbox for that
I can select 'Development Language Only' but it does not give me current translations I already have in Localizable.strings (Czech).
Everything is working fine for Slovak though. I also want to have Czech language to be a default one for English, France etc. That's why I set it up as a development language.