Which option is NOT a method for changing a user's account settings?

Changing a user's account settings typically involves modifications that directly affect their identity, capabilities, and access within the Smartsheet environment. Adjusting user roles allows administrators to define what a user can do within the platform. This includes changing their responsibilities or the level of access they have.

Editing usernames is relevant as it directly alters how a user is recognized within the system, impacting their interactions and visibility. Adjusting user permissions encompasses changing their access levels, which is crucial for maintaining security and ensuring that users have the appropriate rights for their tasks.

Adding a user to a different workspace, however, does not fundamentally change the individual user's account settings. While it may impact what the user can access in terms of projects or sheets, it does not modify their overall account profile or associated permissions in the same way the other options do. Therefore, it is not considered a method for changing a user's account settings, as it pertains more to management of resources rather than the user account itself.