Easily identify transactional emails

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I am looking for a way to sort through our emails to know which ones are Transactional emails NOT marketing.   On the individual contract record it is noted "transactional email" but that is the only way to know which ones are by simply sorting through emails.

 

Some Single send API emails are automated marketing emails and some are transaction emails.  It is impossible to denote from the Marketing Email templates which one is which.