All Vendors are accounted through Accounts Payable. Credit Card and Liability works the same way. Difference is that the A/P have a dashboard to view and a prompt for Due. There is a way but it will cause a mess in reporting and accounting. That will cause double entries or unable to have the actual balance of your Credit Card and Liability.
The problem comes when you create a Bill to show the payable from your Credit Card. If you'll use Credit Card as an account on the service item to bill the payable in the Credit Card. Your Credit Card will have zero balance (will be an issue in reconciliation) while you still have an existing payable amount in the Accounts Payable.
When its time to pay the loan or your credit card, you may refer to these links for the detailed steps: