Hi, apologies for not being clear in the question. I would like that the custom fields from the primary language, English, are never translated.
So if I set up a CPT in English and duplicate it to create the_content() for it in Spanish, when I later go back to edit/update the English custom fields which I create by Metabox, the Spanish language custom fields would also be updated, just like English.
I hope this explains the question better.
Thanks!