It is possible to assign a card to someone in your team without inviting them to join your workspace as a user. The solution is to add them as a Guest user.
This allows them to access the supplementary card(s) created for them, and they will not have visibility on any other parts of your workspace, not even the Applications tab.
To invite a Guest user and assign a card that only they can view, Admins, Team managers, or the application owner will need to do the following:
Go to the Applications tab and select the relevant application. Once you are in the application, you will then need to click on Add new card located under the main card.
Enter the email address of the individual you want to grant access to the card and set the expiry date for the card, ensuring the Guest user can only use it for payments until the specified date.
The Guest user will receive an email with a link to access the application and view their card details.
To formally integrate Guest users into your workspace, Admins can edit their user role in Settings > Members. After that, these users will be able to access the rest of the tabs according to the role they are set as.
Just like normal user management, only the Primary Contact is able to set the user as an Admin.