This is an interactive Azure Powershell script that allows you to add multiple users to multipe roles across multiple subscriptions.
Uses the Powershell GridView to allow you to multi-select users, roles and subscriptions.
- Search Azure AD using display name search strings or email addresses to create a list of users to grant rights to.
- Select multiple roles to apply.
- Select multiple subscriptions to apply the changes to.
Click here --> Technet Script Center post