If you've just added an Etsy sales channel but the shop is in a vacation mode, we won't be able to import your listings. If you need to keep your Etsy shop in vacation mode, you can take it out of vacation mode briefly so that everything imports and then put it back in vacation mode after.
While in vacation mode, stock levels can still be synced to your Etsy shop. The only caveat is that Trunk will have trouble automatically picking up on any stock level changes you make within Etsy itself. In order to get around this, you can manually refresh your Etsy listings from within Trunk.