Depending on whether or not you card charges the foreign transaction fees you won't have any issue making the charge only issue is to make sure that you choose the kind of card you're using. You'll be better off choosing KRW vice CNY since you';ll have a better choice of card types. I just bought a HND-ICN ticket using my US Amex and I've bought others using my VISA and MC from the US site even when it goes through the Japan or Korea sites. I've only had issues when I haven't made sure that my name matches the card exactly.