While working on a project to insert a formatted Excel worksheet into Outlook, we found the formatting kept changing on insert.
We worked around this approach by copying the worksheet into the clipboard, but then found we could not use an existing feature in the Outlook VBO to paste from the clipboard into the message body.
We instead added to our Microsoft Outlook VBO Extension (our collection of homemade goodies) and have been running this since Jan 2024.
I think this code would be a good inclusion in the excellent MS Outlook VBO package that SS&C Blue Prism has provided.