Dedicated IP domains : can MX point to every I'm ?

Hello, On a server different domains with each dedicated IP. They are sending out mail from their dedicated IP. Question : - For the MXs if each domain, can I point them to every ip of the server, or maybe s'y they point exclusively to the dedicated IP of the domain ? - same question for smtp, pip, imap hosts : have they to point to the respective IP of the domain, or is every IP if the server is just ok ? - what about autoSSL certs for secure email CV communication. On witch hostnames are they set in case of domains with dedicated ip ? Thanks for clarifying me