By default, Shopify returns translated metafield values to liquid:
{{ "product.metafields.custom.some_metafield_name.value" }}
{{ "collection.metafields.custom.some_metafield_name.value" }}
When the translation is missing, Shopify returns default language value. When printing locales with missing translation, Shopify throws a “Translation missing” error to notify about the missing translation, so it is easy to check for missing translation for locales, but not for metafields.
How to check if product/collection/page metafield translation is missing? Of course I can see it on storefront, but I need to check it automatically (if translation is missing, use other value instead). Bypassing Shopify’s default behaviour by creating all the metafields as locales is pain, because it would require creating locales for every product and whenever a new product is listed, a new set of locales would need to be created.