This feature was added June 2016.
If a Task is created from the Flex Outlook Plugin it does not automatically recognize any “Copy Down” field values that are present when creating a Task from within Flex itself.
Below is a screen shot of “Copy Downs” that are being used in our Demo site. Remember that the “Copy Down” list will be set up for all types of related items. If the Task could be related to an Opportunity, Account, Contact or any other item in your Flex system. Use [ ] or not. Either will work.
With this new Setting (and an update current with June 2016) you can now include any “Copy Down” values that should be included when the Flex Outlook Plugin processes either “Convert to Task” or “Create Task” to ensure compatibility with the process being completed in either the Plugin or Flex itself.
Setting Name: OutlookPluginTasksCopyDown
Setting Value: Lists of Matched Copy Down Column field values