The list of printers shown in the above link are label printers.
Note the paragraph before the printer list:
You can print your shipping label and packing slip on 8.5" x 11" paper using most standard printers, and then tape the label to the envelope or box. If you want to print on label stock, you can use any of the following combinations of printers and types of label stock: ......
Isn't the Epson Workforce 630 just a standard all-in-one printer?
For mailing within the US, Delivery Confirmation is now called USPS Tracking.