ArcGIS Pro can sometimes take severl minutes to Initialize open editing tools such as Move or Edit Vertices when changes are made to the selection. The 'Initializing Tool' step can sometimes take several minutes after small changes are made to the selection when working with feature services. I recommend that ESRI take a look at this performance issue in future versions of ArcGIS Pro and possibly consider not initializing the tool until a specific command such as 'Remove Vertex' or 'Add Vertex' is selected. This will remove redundant initializations each time a selection changes with the tool ribbon open. The performance increases dramatically when the tool ribbon is closed, but it would allow users to be much more efficient if selection could be changed efficiently while continuing to use the same tool.