Yes, creating an Alias/ symlink will work - for plug-ins, anyway. Has been possible for eons. Not sure about scripts, as it may mess with some scripts' internal logic, but it's worth a try.
Just to be clear, make the alias in the plug-ins folder and point to the public folder you have access to. This will work for plug-ins that reside in the application folder (Adobe After Effects/Plug-ins) as well as for plug-ins in the Library/Application Support/Adobe/Common/app/ Plug-ins folder.
May plug-ins that reside in the common folder will not install anywhere else with the company installers so you'll have to make a workaround for that problem.
Scripts and Animations Presets will run from any folder.
I know scripts will run from any location, but will they show up in the Script menu and the Window menu (for ScriptUI Panels) if they are installed elsewhere?
I'm resurrecting this old thread as I'm now in the same situation as Navarro's, i.e. I want to install scripts outside of "Program Files\Adobe\Adobe After Effects <version>" folder.
I want to be able to install a script on a network drive which is accessible from many artist workstations (AE is installed locally on each of them).
Any help would be appreciated. Thanks!