Translate Custom Post Meta

Thank you once again for this plugin. I hope I’m not wearing out my welcome by asking another question.

I’m trying to set up some Custom Post Types with meta fields, but am not seeing translation alternatives for the meta fields come up in the edit interface.

I’ve checked the relevant CPT’s in the Sublanguage settings, and under Language Options for each CPT, I’ve checked the boxes under Translatable post meta.

The edit interface for each CPT still only shows the Custom Fields underneath, the same for each language tab. I also tried a couple of other themes, but no change.

Am I missing something obvious? Thank you again.