Will a US citizen be charged more purchasing from a Australian Bank link PayPal account

Description

Hi All,
I have a question that is confused the help desk person in Australia.
II have a product listed for sale in Facebook Marketplace, which I want to sell in the US as it is in the US. If an US citizen buys this product and chooses to pay through Paypal, will they be charged any extra fee’s as my paypal account is attached to my Australian Credit Card?
I have a feeling it may just sit as US currency in my Paypal account with them not being charged any extra rate but I don’t know this for sure.
Thanks
Pete