@prabhakar b , You can perform the steps mentioned below:
In Tenant A:
Create a app registration as multi-tenant application in tenant A (eg: TenantAAPI) and expose it as an API (api://app-id/app.read).
In Tenant B:
- Try to access that TenantAAPI multi-tenant application using a user of Tenant B, so that the application gets added to Tenant B as a service principal.
- Once the application TenantAAPI gets added to Tenant B, you should be able to see its entry under the Enterprise Registration section.
- Create another App Registration in Tenant B (eg: TenantBApp).
- In the API Permissions section of TenantBApp, you can add a permission: Add a Permission --> Select an API --> APIs my Organization Uses --> here search for the api of tenant A i.e TenantAAPI
- Once you find the TenantAAPI, Add its exposed permission i.e app.read as it would be listed there.
In this way you can go ahead and make the api exposed in tenant A available in tenant B.
Hope this helps.
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