I’ve been meaning to mention this for a while.
Starting in late 2017 Microsoft started releasing a new version of Outlook Mac 2016 and Outlook for Office 365 for Mac that enables drag-and-drop conversion of emails to tasks.
This feature is similar to what is available in the Windows version of Outlook, but no option is provided to include an attachment in the converted task.
I’ll write more about this in the future.
Michael