You can choose who pays the Merchant fees at checkout on Peerwallet as a seller. Originally you have the Peerwallet fee which is paid by you the seller and you have the Merchant fees which the customer pays, but you can decide to pay your customer's fees.
From the seller configuration page
Sellers --> configuration --> Who Pays The Merchant Fee?
If you select the ME option, this means that your customers checking out from your checkout page would pay at no fee while you are charged the Merchant's fee from the total amount received.
You are selling a book for 10EUR, and your customer gets to the checkout page and selects to pay via Crypto, if the Merchant offering the gateway is charging 3%, this means; your customer would be able to pay exactly 10EUR via the crypto and then you would receive
10EUR - Peerwallet fee - Merchant's fee = Earned value.
We recommend you select to pay the fees and add cost to the product you are selling itself so that your customers should pay the exact amount at the checkout page.