Migrating All Workspaces, Datasets, and Apps Between Power BI Tenants

Sorry I forgot to mention about workspaces. The thing about "migration" is that it's not actually a migration as the definition. It's more creating the most closed structure in another tenant. Thinking that way means that you will be creating scripts to make sure your new structure is similar to the old one.

The script will probably start getting the workspaces and its datasets/reports with a token. You can loop them. Then running a new token auth for the new structure and creating the workspace. You can go workspace by workspace read old, create new. Then content, export old and import new (considering the limitations like I said before).

The creation of the workspace can be as deep as you want. The process could include things like asign a capacity or check the users in the old to add users in the new one with the same permission for the workspace.

Another thing to consider is apps. Sadly, if you are distributing the content with just apps, you can't migrate that configuration.

I hope that helps