There are two config options that have been in every release of Pro/E(Creo) for at least a couple of decades:
search_path
search_path_file
The first will add the path to one directory. You can add additional search paths on separate lines, they will be searched in the order added. search_path_file will load a file that contains nothing but additional search paths.
I never bother with the search_path_file. I put common folder search_paths in the load point config.pro. Then if a project folder needs some additional files from another folder I put the extra search_paths in that working directory config.pro. We always load the working directory config.pro file when we change to it at the start of a session, that way Pro/E always finds all the files.
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