Thanks for the answer.
So, the portable version is not truely portable if some files are copied on the Windows OS partition.
Is there a way to store them in the "Portable folder" (where all files are unzipped in a new sub-folder) and specify the new "access path" for a right loading by Arduino IDE ?
My goal is having a real portable folder of each portable version and avoid any common files between each version. It could be also useful to compare any updates between 2 different versions.