Hi @Ricardo Benton ,
Thank you for reaching out to the Microsoft Q&A Forum. Based on my tests, to enter the verification code and avoid logging in with MFA, please create a Conditional Access policy that makes internal users require MFA and external users does not require MFA. Please correct me if I misunderstood.
Here are steps:
1.Go to Entra Admin Center (you will need to be Global Administrator) -> Protect & Secure -> Conditional Access -> New policy.
2.In the Users section:
3.In the Cloud apps and sections:
4.In the Grant section:
5.Enable policy.
If prompted to Microsoft Login page, if the external user is using @gmail.com, you could still type Google email address and receive the verification code.
I hope this helps. If you have any further questions or need additional assistance, please feel free to ask.
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