Get list of all product variants Barcode (EAN NUMBER) - API

[Laforga-Design]

For a custom made app regarding the order process from a client and a supplier from start untill fulfillment we need to get a list of all variants in a shop. The shop has more than 200 products and more than 700+ different variants with each one a specific Barcode (EAN-number). Looping through all of them is not effective. How can I get this data?