In Taxi, you can give users or teams access to a specific Email Design System on your account. When the user or team creates a new project they will only see the Email Design Systems that they have access to.
To set permissions for Email Design Systems:
Go to the Email Design Systems page
Select the Email Design System you want to give specific access to
On the Email Design System settings page select the Permissions & Sharing tab
Under the Permissions section tick 'Restrict users and teams from using this Email Design System
This will then give you the options to add users and teams
Click 'Add+' to give access to the user or team
The user or team will then appear under the headings Teams or Users
6. Click 'Save'
This Email Design System will now show for the users and teams with permissions