Does fmEcommerce Link (WooCommerce Edition) support Product Variations?

Yes – you can download, update and upload Product Variations. In the fmEcommerce Link (WooCommerce Edition) REST API v1.fmp12 file each Product Variation is another record in the Products table linked to the parent/master Product record. You can set the same attributes that you can via WooCommerce:

In the fmEcommerce Link (WooCommerce Edition) REST API v2.fmp12 file variations are stored in their own table and can be uploaded/download separately to their parent Product record: