See this FAQ:
https://www.toontrack.com/faq/how-do-i-set-the-path-to-my-toontrack-plug-in-in-cubase/
In addition, the Cubase 9 manual should show how to add paths to plugins.
See this FAQ:
https://www.toontrack.com/faq/how-do-i-set-the-path-to-my-toontrack-plug-in-in-cubase/
In addition, the Cubase 9 manual should show how to add paths to plugins.