Your end customers can always use an alternative payment method when DCC is enabled. Some APM are only available in some countries and currencies. This means that even if the APM is not available in your location but it’s available in your customer’s country/currency they will be able to use it.
Example: If your basket is in a different currency (ZAR for example) and you want to offer iDEAL to your users coming from the Netherlands, you can enable DCC so they will be able to pay your ZAR basket in EUR.
For more information about the APM check the handbook