How to retrieve Power Query transformations in a single dataset or connect to multiple datasets ?

Hi DIACHROMA ,

" Find a way to connect to multiple Power BI datasets"

- It is not supported in power bi desktop because connecting to power bi datasets uses Live Connection mode which only allows single dataset connection.

"I am not familiar with Dataflow, could a feature meet my need?"

- Dataflow may achieve this that it can create multiple entities under one dataflow, maybe you can refer: Creating a dataflow 

"Perform my transformations in several Excel files with Power Query and retrieve all the tables already transformed in Power BI Desktop (in this case is it possible to configure an automatic refresh of Excel files on Sharepoint?)"

-You can use the folder connector to connect your several files and transfrom them in power query, if the files are in SharePoint, you can connect to SharePoint Folder, refer:

1. Combine And Transform Data Of Multiple Files Located In A Folder In Power BI 
2. SharePoint Folder 

-In this case, if you want to refresh these files in power bi desktop, just click the Refresh button to get the latest data from files; if you want to configure autorefresh in power bi service, you can set schedule refresh for it which will refresh at some time you set automatically, please refer: Configure scheduled refresh 

Best Regards,
Community Support Team _ Yingjie Li
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