Looks like Microsoft.SqlServer.XEvent.Linq.dll has been removed. It was found in previous versions, including microsoft.sqlserver.sqlmanagementobjects.150.18040.0-preview
Either way, I'm looking for QueryableXEventData which is awesome and useful. When I try to load the DLL from old versions including microsoft.sqlserver.sqlmanagementobjects.150.18040.0-preview, I get
Add-Type : Could not load file or assembly 'Microsoft.SqlServer.Xe.Core.dll' or one of its dependencies. The specified module could not be found.
How can I get this class back? I'm using this version of SMO

Thanks much,
Chrissy