Ecwid product CSVs have the same holes. You do not need an app.

Blank SKU, $0 price, no imageUrl, two rows sharing a SKU. Export the catalog and check it in the browser.

Open the CSV check

How

1. Ecwid Control Panel → Catalog → Products → Export (CSV with sku, name, price, quantity, imageUrl).
2. Open csv-check.html and drop the file. Nothing is uploaded.
3. Fix the rows that cannot sell. A ranked Monday list of 20 is the Store Audit (USD $149) — email the same CSV to info@shopgaps.com.

ShopGaps is not an Ecwid app and does not connect to Control Panel. WooCommerce merchants who want an on-site plugin can use Catalog Audit.