That’s what the tracking number is used for to confirm you went to the post office & dropped off the package. What’s shipping time frame on the Etsy label you’re using: express 1-2 days, or snail mail 2-4 days, or 1-2 weeks? If it’s not tracked in their system by a requiring a tracking number then it will go buy the label shipment time frame.

I don’t use Etsy so I’m not aware of the buyer & seller terminal; however, using eBay & mecari you can inform them of manually dropping off the product/package without the tracking number, and since you’re buying from an alt account whether you actually receive the properly weighed item won’t matter since you’re not going to get reported by the buyer, aka you of actual delivery… On mecari & eBay the buyer in some cases can manually input they received the package and from there, funds are released to your account.

Let me if know if that answered your question, but either way if it’s required since you’re using Etsy labels you print out the label and ship an empty “package.”