Magento 2 Saved Credit Card by Meetanshi lets customer save their credit card details in the Magento 2 database using built in encryption for offline order processing.:

The default offered the feature to save credit card details in encrypted format for offline order processing. However the Magento 2 platform does not support it. To overcome this default limitation, Meetanshi has developed Magento 2 Saved Credit Card extension.

The extension allows customers to save the credit card information in the database using the Magento's built-in encryption mechanism. Use the method when you have a card terminal in a brick and mortar store or have access to a virtual terminal.

Note: It is advisable to check the PCI Complaince standard applying to your country before using the Magento 2 Saved Credit Card module 

* Save credit card details including card type, number, and expiration date.

* The extension saves the credit card details in the encrypted format.

* Use the saved information for online and offline orders.

* For offline orders, use the Magento built-in CC validation

* Display custom title for the payment method.

* Display credit card logo on the checkout page.

* Set status for the new orders placed using this payment method.

* Allow selected credit cards to allow using this payment method.

* Allow selected countries to use the Saved Credit Card payment method.

* Let admin see the customers' credit card details.

* Admin can wipe out the credit card information after processing the order.

* Collapse the credit card details view by enabling the mask mode.

* View the credit card details using the "Show" link in the backend.

* Display additional details on the checkout page.

* Set conditions for the order total to use the saved credit card details.

* Let customers check the payment details from the "My Account" section.

* The admin can navigate to Sales > Order view in backend to see the payment details. 

For more information, visit https://meetanshi.com/magento-2-saved-credit-card.html