My shop, AdamFamilyOddities, only sells digital items at the moment. I've been using the money from the digital sales to buy items to create physical items to sell. I ordered 200 polymailers and a pocket digital scale already. I also have a Zebra ZQ520 that my father gave me with the paper roll in it and without any cords. It is a thermal label printer and should have the ability to print the stickers needed to work with Etsy. I'd only have to buy the 4x6 sticker labels.
I personally don't know how to properly connect the device to anything despite me being someone who graduated from a school for computers, technology and cybersecurity in 2015. (Probably because I've never had my hands on a portable barcode scanner before.) It seems like the best bet would be to connect it to my laptop and figure out drivers, but I can't seem to find out any. I've tried connecting it to my iPad which connects to my Square reader, but it doesn't want to work properly and I've connected it to my OnePlus7 Pro and got it print, but not something properly, but it did print with the use of the Zebra app. I personally think that figuring out how to use it on my laptop not needing the use of an app so that I can fully work with it better would be best. I have a Dell Latitude 3480 with the most up to date Windows 10 operating system on it. I can connect the device to the laptop, but it doesn't appear as a printer.
Images of the printer and the screenshot of how the device connects to my laptop (since all my screenshots are above 1 byte and it's multiple images): https://docs.google.com/document/d/1e8OhW3JAABX9ejZzB0ooCT65-Efx4Ngco3MOz0-UTqE/edit?usp=sharing
I personally have a Dymo printer, but what helped me with setting it up was watching some YouTube videos and seeing how it was set up and the steps someone used to get it done.
I've personally tried that myself, but it seems like finding it for my specific printer is scarce.