Power BI, Dataverse, Project Online help

My client uses Power BI to report on a portfolio of projects in Project Online. They would like to be able to view detailed reporting over time within Power BI. They have a ton of Power BI Pro licenses. We would need some place to store the historical Project Online data, and this is where I'm confused. 

I'm thinking we could use Power Automate (with a Premium license) to move data from Project Online to our data source, but don't know A) what that datasource should be or B) what the licensing requirements are. Is Dataverse a good option? Is Azure SQL overkill? We're talking 100+ projects, with data captured once a week to an external datasource so we can report against that datasource instead of Project Online. I think our current Power Apps license gives us Dataverse access (and so would the Power Automate license I believe). Would that be sufficient for this sort of weekly data capture? We would then connect to Dataverse via import once a week rather than direct query, so it seems like the volume would be pretty low. If it's helpful, our current model is about 80MB, with plenty of room to trim and optimize. 

I hope this is enough information for a clearer answer than I've been able to find on my own. Thanks in advance.