Apart from longtime permanent solutions already discussed here, isn’t it possible to put materials in separate folders, and into the “main folder” for each material also folders for plugin-renders, and finally, add redirect links (“symlinks” *) from the plugin render to this centralized folder structure?
An awful lot of handcrafting to create such a folder structure, but if it would work, then you yourself could make it work in a day or two.
// Rolf
* HardLink ShellExtensions for Windows
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