Step-By-Step: Migrating The Active Directory Certificate Service From Windows Server 2008 R2 to 2019

If anyone wants to see a more complete version of the steps, including exporting the list of published templates on the legacy server and copying CAPolicy.inf if required, then the old PFE blog on how to migrate is still the easiest and most complete guide to follow: 

https://www.sysadmins.lv/retired-msft-blogs/xdot509/upgrading-your-pki-from-windows-server-2003-to-windows-server-2008-r2-part-iv-migrating-enterprise-cas.aspx

I don't know why this article and the https://learn.microsoft.com/en-us/troubleshoot/windows-server/identity/move-certification-authority-to-another-server weren't simply updated  and expanded from that, since the basic steps are exactly the same. The MS Learn article includes some more detail and troubleshooting advice, but the layout is a little confusing - someone might not realise that there are different steps between recovery to a server with the same name and a server with a new name given in that document (naturally, the second option is not preferred).