First of all you should export the products from Etsy to csv file (as far as I know it's free of charge). To do that you should perform following steps:
- Go to your Etsy account
- Follow Your Shop --> Shop Settings --> Options
- Open "Download data" tab
- Click "Download CSV" button.
You should use this file in the EasyImport ‑ Etsy Import app. After uploading it in the app you'll be able to check the listings, select the necessary products to import, and adjust other settings.