Unfortunately this feature isn’t part of Webflow natively as far as I know.
I’m not sure if you have access to form submissions via the API — if so, an automation platform like Make could be an option — but you can always look into third-party form endpoints if this functionality is necessary for your client.
This isn’t something I’ve ever needed so I’m not sure off the top of my head if it supports it, but other folks have recommended Basin: