For showing live data of a sharepoint, I'm not aware of any approach other than calling Power BI REST API.
You don't even have to be a pro user if you have coding skill and know how to extract that data from Sharepoint programmatically. And then you can push data from sharepoint to Power BI service, say every 10 minutes. Check Push data into a Power BI dashboard.
Also check the Power BI REST API limitations.