HunchBluntley: I think I've had that in the past (can't remember if it was PayPal or my bank doing it in my case, though). I wouldn't call it a "problem", as it didn't particularly surprise me when I noticed it, but yeah. However, I just checked both my PayPal receipt for my most recent purchase from GOG, and my recent bank transactions, and neither showed any surcharge; and I'm pretty sure a lot of past purchases haven't had one either, so I don't know what the deal is.
EDIT: I'm guessing it's related to your bank/ the card you're using, unless you actually see a notice somewhere that says it's PayPal adding the surcharge.
Yes, you are right. It is my credit card issuing bank that is charging foreign trans fee. (I called the issuing bank this morning and confirmed they are the one charging me foreign trans fees).
Also I don't see foreign trans fee listed on my Paypal's transaction lists.
I also remember I changed the credit card linked to my Paypal account a week before started making more purchases on GOG.
Both my old card and new card issuing banks have 1% foreign trans fee policy but the old card never charge me foreign trans fee for GOG purchases if I make purchases via Paypal.
Anyway, I can always use my Capital One card to avoid foreign trans fees.