Server notifications should be sent using a freely configurable SMTP server and port
The sender's address of Plesk notifications can be set since Plesk 18.0.45, but it is also desirable to being able to configure the SMTP server, port, loginname, password and encryption scheme for such notifications. For example, some environments don't allow mail-out through port 25.
MR. noone01 commented
This should be done years ago....