The first 6 digits of a credit card are called the BIN number. Based on this BIN number anyone can tell who the issuer of the credit card is. Paypal's automated system knows EXACTLY what VISA youll be adding and to answer your question - YES it WILL cause problems trying to add a US based card to a EU account. You will most likely not be able to do so anyway as it will not pass the AVS (address verification system).
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AGED SUPER HIGH LIMIT ACCOUNTS: 10,000/$1,000,000 and 25,000/$500,000