I know of 2.
If you include "2AF" as a tag for a login, that login will not show up in the Two Factor Authentication Watchtower category. If you include "http" as a tag for a login, that login will not show up in the Unsecured Websites Watchtower category.
Are there any other useful tags available or is that it?
1Password Version: 7.6.787
Extension Version: Not Provided
OS Version: Windows 10
Sync Type: Not Provided