Thank you for posting your query on Microsoft Q&A. From above description I could understand that you are looking to block a specific browser access to cloud applications via Azure AD.
We could not block a specific browser via Azure AD:
- For android and iOS devices it is possible to force using Microsoft edge only via Require approved client app, this would force the user to use only edge and other Microsoft apps.
- For Windows devices we must use AppLocker and deploy it via Intune custom policy.
Please do let me know if you have any further queries.
Please "Accept the answer" (Yes), and share your feedback if the suggestion answers your query. This will help us and others in the community as well.