Is it possible to determine the traffic consumption per e-mail address?

Unfortunately, the used traffic can only be determined exactly for the entire domain. Although you can view the traffic of the e-mail address using the incoming and outgoing message size in the log search, but this does not reflect the total traffic consumption. The values in the log search only show the size of the message content. The value displayed in the domain statistics includes all data consumption that occurred during the SMTP transaction, pre-data and post-data.