Not near my music PC at the moment, but it should be possible.
(Search your harddrive for pluginmanager.xml
It is something like C:\Users(xxxxuersnamexxx)\AppData\Roaming\Steinberg\Cubase 8.5_64\PluginManager.xml for your old version)
There is an XML file that stores the collections.
As a band we use it, to copy collections between band members (plus it is helpful for checking which plugins some of us don’t own, so we know not to use them in shared tracks).