Reza Rad gives us a method to modify linked entities in Power BI dataflows:
It is not possible to change a linked entity in a dataflow in Power BI. Linked entities has to be modified only in the dataflow in which they are created. However, sometimes, you need to do a small modification to the linked entity in a chained dataflow. There is a very simple trick, In this article and video, I’ll explain how you can do that.
Read on to see how.