You are able to add products Swift Distribution Flat with Stock Sync. Just choose on Swift Distribution Flat template after choosing to add new products to store. 

1. Go to Setup New Feed > Choose Add new products to store.

2. Choose or search for Swift Distribution Flat template.

3. You need to fill up the Username and Password from your Swift Distribution Flat profile.  

4. Click Next to the field mapping section.

These are the available fields that can be added with Stock Sync. 

SKUVariant SKU
priceVariant Price
quantityVariant Inventory Qty    
product titleTitle
BarcodeVariant Barcode
DescriptionBody (HTML)
Inventory PolicyVariant Inventory Policy
Product Type (Custom)Type
URL / HandleHandle
Product ImagesImage Src
CostCost per item