I got Cubase 9.5.4 setup on Windows... I have been doing all kinds of things to see if I can create a problem (re-installing, rescanning, messing up the database, moving patches, and generally giving it tough startup conditions), and Waverazor just keeps working fine on my system. Frustrating that I cannot reproduce this issue.
Another thing to try would be to just install the Waverazor plugins (without FX) and remove (or temporarily rename) the folder containing the patch database and settings and see if a rescan in Cubase will be happy with that.
1. Uninstall Waverazor (C:\Program Files\MOK\Waverazor\uninst)
2. Rename C:\Users\<user-name>\AppData\Roaming\mok to C:\Users\<user-name>\AppData\Roaming\mok_temp
3. Install VST/VST3 of Waverazor
4. Run Cubase (and possibly rescan if needed)