If the store you want to sync to already have listed products, there are a few things you have to ensure before you start exporting your products.
Once adding a new target channel to our service, ExportYourStore will bring all the products you have already listed on the channel and match them with your source products by SKUs.
There are a couple of scenarios
1. The product exists on both source and target channels, with the same SKU.
In this case, ExportYourStore will recognize the products and link them together, so they'll be synced properly. On our dashboard it will appear as "Linked & Synced".
2. The product exists on both source and target channels, but with different SKUs.
In this case, ExportYourStore can't recognize that it's the same product and duplicates might appear.
One suggested option will be to rename the SKU on the target to fit the source SKU.
* If you don't have SKU on the source, ExportYourStore has a great tool helping with SKUs conifgurations. Read here for more information.
3. The product exists on target but not exists on the source.
In this case, ExportYourStore won't change products that was not linked.
This means there are no effects on those products.