eBays partner will authenticate them if they sell over £100.
However:
1.What if the item does not pass authentication checks?
If the item’s authenticity cannot be verified or the item is not consistent with its listing, the buyer will be notified and will be issued a full refund to their original payment method.
2.You acknowledge and agree that if the Authentication Partner cannot verify an item’s authenticity, a refund will be issued to the buyer and you shall cooperate with removing the item from marketplace circulation.
Now the second point to me reads as though buyer receives a full refund and seller doesn't get shoes back.
https://pages.ebay.co.uk/authenticity-guarantee-sneakers/
