Hi juni dev,
Thank you for posting your query on Microsoft Q&A. I am Saiteja from Q&A will be assisting you with your query.
As per your query, I understand you would like to have a migration approach in external ID and like to know the possibilities of JIT password verification as similar as B2C.
Currently External Entra ID is still emerging, and our team is working on it to provide the best features in nearby future. Right now, we do not have a feature for JIT password verification in External Entra ID in any possible ways. You can always what's new in External Entra ID using the following link: https://learn.microsoft.com/en-us/entra/external-id/customers/whats-new-docs
I hope this information is helpful. Please feel free to reach out if you have any further questions.
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