It si possible, with at least two ways, since your aggregate is ONA.... This will be the simplest though might be a bit costly after trial time...
- in your XLSForm, add one question that always evaluate true e.g.:form submitted
- next sign up for ONA rapidpro
- design a simple flow that listens to the form in ONA
- Link to ONA form to the rapidpro flow
With that everytime a submission is sent, an email notification will be sent to a list of emails that can also be embedded in your form
All the above depends on what ONA plan you have, plus the rapidpro hooking API maybe charged per use.
The second method would be to trigger mails from your backend database....only works if you have a local aggregate that you can control... possible for hosted ones but haven't done it yet...
Let me know If the ONA solution interests you, I can share with you one sample form on ONA to see how this works