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The fuck is going on in this thread?
Gamefreak's ingame canon is contradicting itself all the fucking time, why is this even being discussed?
There is no right answer, just incompetence.
Anime introduced the :) face, merchandise picked it up years later and since then it has been used for all the Ditto merchandise because it sells well.
Anime and games always depicted Dittos transformation as actual copies without the :) face.
Gamefreak could change this any time by making adding sprites for all 800+ Pokemon with formes with the Ditto face, but this will just take up space and would cost them time and effort, probably wont ever happen.
