This feature is exclusive to Gelato+ or Gelato+ Gold customers.
We've not yet linked Etsy's, Shopify’s, or WooCommerce’s gift message feature to Gelato’s Product Personalization tool. For now, your customer's gift message cannot be automatically printed on the Packaging Insert, yet if you are using the manual order approval function, you can modify the Packaging Insert based on your customer's input (e.g. a special gift message).
You can read more about the best practices to approve your orders manually here.