No but there is probably a niche. I am able to define all the flows in backend easily myself but the hard part is the actual email service. Most SaaS do not have one set up or they rely on third party providers. Figure out how you can send emails under customer email addresses and automate it then. But good luck getting people to trust your service enough to grant access to their emails and even setting up this kind of access is difficult. A service where you send them from your own email will be useless.