Hi, 
I would like to know how long it take for thid pop to stay in salesforce once the EAC configuration is enabled?Its been 2 hours now and I am still seeing the below pop up.Also the user having it setted up does not have many contacts or emails associated with it, so i barely think that is causing the wait time to be longer.
"We are getting Einstein Activity Capture ready for you. While you wait, choose who you want to share emails and events with.Update Sharing Settings"