If the item was purchased under the Global Shipping Program, the import fees would be separately refunded by Pitney Bowes, if they were part of the refund process.
The seller would not be refunding import fees, since he never saw them and may even be unaware that you were charged them.
Or are you referring to the cost of returning the item to the seller?
The seller is not required to refund return shipping by eBay or Paypal. If the reason for the return is seller error (eg you ordered a red sweater and got a blue one), it is a Best Practice for the seller to refund return shipping, but again, no requirement.
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