Order confirmation mail use order object which don’t refer to your product object therefore you can’t access product metafield here.
However it’s feasible by doing some tweaks in theme files, let me know if you are interested to work on it.
Goal: show a product metafield (item_location) beneath each product line in the Shopify order confirmation email.
Context: Notification emails primarily use the order object (data for the placed order). The requested data lives on the product object as a metafield (a custom field attached to a product).
Key developments:
Current status:
Outcome: No confirmed working solution yet; discussion remains open. Open question: the exact Liquid scope/path needed to output the product metafield for each line item within the order confirmation template.
Order confirmation mail use order object which don’t refer to your product object therefore you can’t access product metafield here.
However it’s feasible by doing some tweaks in theme files, let me know if you are interested to work on it.