I've been stuck trying to connect my Webflow store with a shipping service. Already tried Shippo and Shipstation, both through Zapier and via CSV order uploads.
The main issue with Zapier seems to be the way address information is formated (feeds as a long stream of information). You can get around this by adding a Formatter action (but it's somewhat complicated). Another issue is that the streamed data is missing addressee name (not always same as the customer) and, importantly, the product SKU and weight/dim specifications. Some shipping options require that information.
The main issue with CSV is the inability to choose information fields. Some critical info (same as with Zapier, above) is missing.
This is a crucial step in ecommerce. I can manually copy/paste the information onto my shipping dashboard, which I'd like to avoid.