Will you elaborate on what exactly you are referring to?

When you send an email with Mailpoet - the date shown in the email is the date the email is sent.

Are you asking for a "shortcode" to show the date within the email you are sending? Is yes, that is already possible, read here - https://kb.mailpoet.com/article/215-personalize-newsletter-with-shortcodes

Note - It is easier to get support and/or your feature requests taken more seriously if you explain in detail what you are asking for.