I know nothing about the OpenVino Plug-in (it is only available for Windows, and I’m on Linux).
Vocal Reduction and Isolation is still included though the manual says it’s no longer included.(?)
The Vocal Reduction and Isolation effect is a Nyquist plug-in that was previously shipped with Audacity, so it is probably left over from your previous version of Audacity. As far as I’m aware it still works on Windows.
In Audacity, go to Preferences->Modules and change ‘mod-openvino’ to ‘Enabled’. Then close & re-open Audacity. This was briefly mentioned on the last page of the installer, but perhaps you missed it.