You’ll notice that when the email address placed in the footer is clicked, your mail client opens and a new email destined to that email address is created. In order to change the recipient email address to yours, to fit the actual email address being presented do the following.
Navigate to the Divi Library within the admin dashboard and open the Global Footer layout. Note that at the bottom of the left column there is a Code module. Open it and change email@example.com to your email in the following line:
window.location = "mailto:firstname.lastname@example.org";