Is it possible to embed Domo in my portal as a designer (not only viewer) with white-labeling

There is an option to help you. It is called the Edit experience from Domo Everywhere. Accounts are created for each external team. SSO integration is routed through the Domo Identity Broker. Each user is mapped to their correct account based on key attributes that in their user profiles in the host system. The Identity Broker is embedded and the entire edit experience feels native and looks like a seamless with the host website or software. All edits are saved and shared only with the other users you approve for that account. Thousands of accounts can be created on your own through the Customers tab in the Domo Everywhere section of admin. This is the fastest growing part of Domo Everywhere and is used heavily by many of our largest customers.

Here is some example documentation on implementing the edit experience: https://developer.domo.com/docs/embedded-capabilities/embedded-capabilities

Here is our latest webinar comparing the View, Edit, and Connect experiences: https://youtu.be/sP6KGjnIsPQ

Here is an article on how Sony does this: https://diginomica.com/how-domo-powers-partner-analytics-sony-interactive-entertainment