These seem to be all Python addons, so the proper installation location for those is not under C:/Program Files. There’s one in /Documents/Visual Components/version/My Commands. That probably does not require admin rights.
Please see this thread for installing Python addons:
FAQ - Python addons in different VC versions - Extensions and Python Add-ons - Visual Components - The Simulation Community
Plugins made in .NET (distinguished from .dll file format) then belong to the installation folder under C:/Program Files, but that’s a different story.