The only credit card I have heard of that has absolutely no international transaction fees is the 28 degrees mastercard. I think it used to be Wizard, but changed over a couple of years ago. I have one, I don't know what the interest rates are like but if you deposit your money into the account before you go, you are only using your own money anyway, so no interest. I highly recommend it, no cost to access your money whatsoever, you can use it for purchases with no charges as well as getting cash out, plus you always get the current market exchange rate.

I don't like travelling with large amounts of cash, so with this card I just withdraw what I need as I go