A product can't be listed on Etsy without a description. There are two ways of updating descriptions on Etsy.
a.) The first one is to provide the description from the Shopify store.
b.) Then choose the “Sync from Shopify” option from the CedCommerce Etsy Integration App’s “All Products” section.
c.) Sync the description then try to re-publish the product on Etsy, then changes will reflect to Etsy.
Or
a.) You can update the description directly from the App by clicking on the pencil icon.
b.) Click on the “edit option” to provide the description.
c.) Disable the “auto-sync” setting for “description” from the “Product management” setting of the App and then publish the products from the "All product" section of the App.