To send the submission email to a different email address you will need to turn off the default notification and send setup a custom email instead.
1. Disable the custom summary
To disable email notifications on new submissions, go to After Submission → Emails in the form editor and toggle off "Send me an email summary on submission".
2. Add a custom email
In Emails, click "Add Email +" under custom emails.
Enter in the desired recipient under the "To address", and add a subject line. For the "Content of email" field, select "Submission Summary" from the dropdown.
When you're ready, click the "Add Email" button to save the custom email and put through a test submission to verify that it is working correctly.