Hi,
The simple answer is "it depends".
There is no distinction per country for credit cards support.
If a Japanese credit card has either the "visa" or the "mastercard" seal on it, almost any payment gateway will accept it.
If the card has the JCB seal on it, then there is less choice. Apprently, Skrill and Adyen supports such credit cards:
www.about-payments.com/knowledge-base/method/jcb
But I'm sure plenty others that we list in our "payment plugins" section of the documentation have support for JCB cards. Of course, the best is to contact the payment gateways in order to confirm that with them as they know better than us what type of credit card they support.
