SmartMLS does not encourage, nor do we facilitate, agents bombarding one another with unsolicited messages through our MLS products. This includes using Matrix to create/send mass emails or mass mailings to individual agents. To that end, there is no way for a user to create a mailing from an Agent search in Matrix. You cannot even create a custom export using Agent information.
However, you are still allowed to start a mailing to specific offices within Matrix. You can create a Custom Export with office mailing address information, then perform an office search for your desired area(s) and merge the results into your custom export. At that point, you would have to save that export to your PC and then create a mail merge in Word in order to create/print mailing labels.