Hookdeck developer advocate here, Shopify will only return the metafield related to the order that triggered the webhook. If the order does not have any metafields, the webhook payload would be empty. To attach metafields to orders check out the official shopify documentation here.
If you need more help dealing with your webhooks, https://hookdeck.io/ is a perfect solution that makes dealing with webhooks in your applications easier.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…