As long as they’re UB compatible, I just take the newest plug-ins/shaders can copy them over into a copy of the older plugin/shaders folder to and then replace all the older versions with the new stuff from the current installation. Then take that copy of the old folder (with new updates) and use it as your new sockets folder. It should now contain a copy of all your custom purchased plugins, plus updates of all the latest stuff.
What I’d really wish EI would do would be to support folders in the plugin menu to help classify different types of plugins. Either that or preferences to assign or route plugins to a specific folder as defined by the user.