Attention! With this post I am not saying it is a wise thing to do but nevertheless you might need it for testing purposes.
Thanks David and Naoya!
On a Windows Server 2016 Datacenter Edition (with GUI) open the cmd line and type:
dism /online /add-package /packagepath:"C:\Windows\servicing\Packages\Adobe-Flash-For-Windows-Package~31bf3856ad364e35~amd64~~10.0.14393.0.mum"
(BTW. Adobe Package is already on disk. You just activate it)
The results should be:
after the reboot verify in IE:
and it seems we even get security updates just like for flash in IE on Win10: