Hi
Based on my test, if we only retrieve data from the Azure SQL database in Import mode and enable daily refresh, it doesn't require Pro license.
To understand the difference between Power BI pro and free better, you need to know what's the pro content firstly. You can see not all data sources and refresh can be available to free users. If you share the dashboard with other users only have free Power BI features, your recipients just need a free Power BI license to view the content. See: Licensing requirements for sharing.
Best Regards,
Qiuyun Yu