From an RMA or 'Return Order' within D365 F&O the action of 'Send Return Order' is not hooked up to Print Management, nor are there setting within A/R Form Setup module to setup Print Management for the Return Order form.

When sending return orders to customers, it is required to fill out an email address manually every time a Return Order is generated.

If this form was added within the print management settings it would be easy to setup email addresses on customers with a purpose of 'Return order' and have the system send out the return order to the customer just like how Sales Order Confirmations function.