Windows
On Windows, you may uninstall plugins using Windows Add or Remove Programs, the SSL uninstaller app in Program Files, or by removing individual instances from the following folders:
C:\Program Files\Common Files\VST3
C:\Program Files (x86)\Common Files\VST3
C:\Program Files\Common Files\Avid\Audio\Plug-Ins
C:\Program Files(x86)\Common Files\Avid\Audio\Plug-Ins
C:\Program Files\VSTPlugins
C:\Program Files\Steinberg\VSTPlugins
C:\Program Files\Common Files\VST2
C:\Program Files\Common Files\Steinberg\VST2
C:\Program Files (x86)\Steinberg\VstPlugins
C:\Program Files (x86)\Common Files\Digidesign\DAE\Plug-Ins
macOS
You may manually remove individual plugins from the following folders:
Macintosh HD\Library\Application Support\Avid\Audio\Plug-Ins
Macintosh HD\Library\Audio\Plug-Ins\Components
Macintosh HD\Library\Audio\Plug-Ins\VST3
Macintosh HD\Library\Audio\Plug-Ins\VST