qemu-kvm-2.11.2-5.18.1.x86_64
[...]
I found a table on https://access.redhat.com/documentation/en-us/red_hat_virtualization/4.3/html/virtual_machine_management_guide/cpu_hot_plug
saying that hotplugging is possible but no hotunplugging.
But i don't know how recent this information is and if RedHat uses libvirt/qemu.
RHV uses a special version of qemu-kvm named qemu-kvm-rhev.
oVirt, the upstream product of RHV, uses a rebuilt package named qemu-kvm-ev.
Eg in oVirt 4.3.8, that is the latest stable release available right now and should apply to your doc link limitations is qemu-kvm-ev-2.12.0-33.1.el7_7.4.x86_64
What is the OS of your hypervisor?
In case of CentOS 7 and not a production one, you could enable the repo from CentOS-SIG-Virtualization like this:
A repo entry is this one below:
Then deinstall qemu-kvm and install qemu-kvm-ev.
I don't remember if yum would detect qemu-kvm as an "obsolete" version of qemu-kvm-ev, probably yes and in this case you would only need to run
yum install qemu-kvm-ev
and it will replace the old.
Browse the repo packages in case, because it would bring in for example also another version of seabios (I don't see libvirt packages in between).
But anyway for your special case also with qemu-kvm-ev it seems no Windows OS is supported for hot unplug.
HIH,
Gianluca