All emails you have created or used in automation workflows can be found and edited on the Messages tab in the left-hand menu in Engage. From here you can both edit and delete automation emails from your tenant.
Go to the Message tab, select Email and go for the option In Automations to open the automation email list.
You can search for specific emails and filter the list on automation status in the dropdown at the top of the page.
Beside each email in the list, you can see you can see how many automations that email is currently in. Clicking on this number opens an overview of which automations and what state these are in.
If you want to open an automation, click on it in this overview. Click on the close button to return to the email list.
If you want to edit an email, you can simply click on its name in the list. Keep in mind that your updates will affect all automation flows the email is part of.
Any email that is not included in any current automation can be deleted. Hover over it in the list and click on the trash bin icon to do so. The choose Yes, delete in the popup.