Assuming you control DNS for all the domains
In our case, yes we do. Host and all domains use external DNS which is easy to configure
Seems like a headache to me
If.. you have zillions of domains, yes, as we have said already, but otherwise, no, just a lot of patience required that's all.
We never need to login to Domain:8443 anyway, but... we can if we want to, without any certificate problems
Host:8443 gives access to all domains and works perfectly, which is why we don't bother. The reason that
@Jmz wants to do this? You would need to ask him why i.e. what he wants to do, once he achieves this.
The purpose for us, FWIW is different. It's to do with accuracy of domain mail / host verification. Securing the host with a *WLE Certifcate that includes all the hosted domains/subdomains, means that this becomes much easier. As far as we're aware, Plesk don't have their own solution for this (other than the obvious multiple IP's) meaning, there will always be a mis-match involved and reported (somewhere) if... domains are using their own mailservers, which are handled by the host / host IP. As you know better than us, you can use many, different, but all very accurate online tests e.g.
Secure Email for verification checks etc. All of these will provide results showing any issues like this, very quickly