Hi Johnatan,
Both the ability to perform full/partial refunds and recharge the credit cards would depend on the payment method you choose.
Here is the
list of what each payment method integrated with X-Payments can do.
Refund column speaks for itself. As for recharging, the payment method has to have the check-mark in the Tokenization column.
And, of course, you don't have to log into X-Payments backend to handle all this - X-Cart does everything via API.