Problem? I am able to translate the product fields (plugin's custom post type) but in the admin dashboard I see all languages together. They are not split between languages unlike the products, for example.
Do you see a language switcher on top admin bar (like shown in the attached image)? If yes, can you try switching to a language (other than All Languages option)?
If that's not the case, assuming that the screenshot you showed is listing custom post type content (i.e. the fields or field groups you mentioned), can you try only with WPML, WooCommerce and the said plugin? while deactivating all other plugins.
Remember to take a full backup of your site and database before proceeding.
Please let me know and I'll try my best to further assist you on the matter.