Hi Prasad,
For triggering external emails for the workitems sent to SAP Inbox , you need to configure extended notifications in tcode SWNCONFIG , for the required workflow template or task or step id.
And then schedule the report SWN_SELSEN to send the mails by reading the configuration done.
You could follow the below link for hints on what configurations are required.
**************** - Extended notification configuration
For Engineering Record , the Workflow template is, WS00100012 . You can try to configure for the same in the above tcode and it should send mails for the workitems.
Hope this helps
Thanks,
Rini