Your organization uses MFA with the Per Authentication usage model. After acquiring another company and adding their users to Azure AD, you need those users to be covered by the Per Enabled User usage model. Solution: you change the existing usage model through the Azure portal. Does this solution meet the requirement?

This solution does not meet the requirement because the Per Authentication usage model and the Per Enabled User usage model are legacy MFA models that are no longer directly configurable or switchable in the Azure portal. Microsoft now primarily uses Conditional Access policies to enforce MFA, which is a more flexible and robust approach. While older tenants might still have users configured under these legacy models, you cannot simply change the "usage model" in the portal for new users or to switch between these models. To ensure the newly acquired users are covered by MFA, you would need to implement Conditional Access policies that require MFA for those users, or enable MFA directly on their user accounts, which would then be managed under the current licensing and enforcement mechanisms.