AllSync & AllDup

I want to make duplicates of files with the same extensions by renaming (in fact resetting the extension with another extension).

Is it possible with AllDup? (even if possible with AllSync, I cannot get AllSync installed at corporate PC, so I can only use AllDup's portable edition)

For example:
D:\%1.jpg is duplicated as D:\%1.jpeg

Im not sure i understand you correct but AllDup doesnt create or make duplicate files.
AllDup find and removes duplicate files.