You can use the Le New Black Connector to export Products from Zedonk to Le New Black.
The Style + Fabric + Colour makes the Product ID within Zedonk and this will create a unique product in Le New Black.
If your Products already exist on Le New Black, please make sure to match up the Barcodes per size in each system.

Please note: We recommend creating Products from Zedonk and exporting them to Le New Black.
If you choose to create Products in Le New Black by Variants - you will not be able to perform a Data Export (an export of Product and Customer Information). You will only then be able to use the Connector for Importing Sales Orders.
Allocate Barcodes to Products in Zedonk for Export Products to Le New Black
You can use Zedonk to generate Barcodes: Barcodes - Settings
Or
You can also use Zedonk to allocate your GS1 Barcodes: Barcodes - Entering GS1 Barcode Range
If Products already exist on Le New Black
You can first export your Barcodes from Zedonk: Barcodes - Data Export / Import
And then Copy these Barcodes to corresponding Product Sizes in Le New Black within Inventory by SKU