Well, as far as I am aware, you can't. There are apparently tricks, for which I have added some links below. The question is why you would want to do this? To my mind you would be better off writing the data out to a file - and have the full functionality of a file - and attach that to an email.
https://communities.sas.com/t5/SAS-GRAPH-and-ODS-Graphics/Embed-an-image-in-Outlook-email-sent-using-SAS/td-p/159267
https://communities.sas.com/t5/ODS-and-Base-Reporting/Embedded-image-in-HTML-email/td-p/60268
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