Hi @MICHAEL PERALTA, GIT , please follow these steps and let me know if they help:
- Set up the external Azure tenant as a SAML IdP in your Azure AD B2C tenant. You can refer to the Set up sign-up and sign-in with SAML identity provider using Azure Active Directory B2C guide for a detailed explanation on how to do this.
- Once you have set up the external Azure tenant as a SAML IdP, you can add it to your user flow or custom policy. You can find more information on how to add an identity provider to your user flow or custom policy in the Add an identity provider to your Azure Active Directory B2C tenant guide.
The linked guides should provide enough information to solve this. If not or if you have more questions about anything let me know and I can help you further.
If this answer helps you please mark "Accept Answer" so other users can reference it.