I tried that recently with windows server 2016 standard evaluation and it returned the message this edition cannot be upgraded.
Windows server 2016 standard evaluation this edition cannot be upgraded.
During this period all features of windows server 2019 2016 are available to you.
But on one server it went on going for 16 hours and i had to eventually wipe it out and install fresh with server standard disc on windows server 2012 though it used to be smooth.
Always go with the non evaluation disc on 2016 the best idea.
Fortunately upgrading is as simple as using the command line.
If the server is running an evaluation version of windows server 2016 standard or windows server 2016 datacenter you can convert it to a retail version as follows.
If the server is a domain controller you cannot convert it to a retail version.
In this case install an additional domain controller on a server that runs a retail version and.