Email reply to adddress different from hosted domain

I have setup erp on a subdomain say erp.foo.com

I have created users with user1@erp.foo.com they are getting email to user1@erp.foo.com to which no mailserver is connected I want the reply address to someuser@abc.com

How can I setup that ?

Sorted this by creating the mx records for subdomain and using a free mail forwarder Free Email Forwarding for Custom Domains | Forward Email

I don’t think you can set this up out of the box. You´ll need to configure that via an email forwarder