Before setting up the Shopify plug-in on Zetpy, you firstly need to set up the Zetpy app on your Shopify. This will also give you the Shopify API Access Token. This tutorial will show you the step-by-step guide.
To sync your products from Zetpy to Shopify, you need to create Category (Collection) in your Shopify store. Only then you can add product in Shopify plug-in.
Only NEW products from Shopify online store will be imported to Zetpy. The existing products in Zetpy will not be imported again.
Shopify Private apps are deprecated. However, it still can be used for the existing Zetpy user. From now on, all new users have to use the new Admin API Access Token to authorize the Shopify account.
How user can add/remove Variation SKU in Shopify Online Store. After that, find the item ID and share us for re-importation.