Mail Clips is a menu bar app for copying Mail.app message properties of all selected messages to the clipboard.
Copy all headers, subjects, recipients, senders, content and more from each selected Mail.app message to the clipboard as a list of values to import into another app.
The following message attributes are supported when copying:
Copy All Headers : All the headers of the message
Copy Content : Contents of an email message
Copy All Headers and Content: All the headers and content of the message
Copy Date : The date a message was received
Copy Time : The time a message was received
Copy Header Message ID : The header message ID string
Copy Mail Message ID : Mail's internal numeric message ID string
Copy Source : Raw source of the message
Copy Reply To : The address that replies should be sent to
Copy Sender : The sender of the message
Copy Sender Name: The full name of the sender of the message
Copy Sender Address : The email address of the sender of the message
Copy Subject : The subject of the message
Copy Recipient Name : The name of the first recipient of the message
Copy Recipient Address : The address of the first recipient of the message
Copy Summary : Sender, subject, date, time, recipient and content of the message
Try the demo. Fully functional.
Note: This is legacy software and requires macOS 10.14 Mojave, the last macOS that supports 32 bit software.