No. There are some moves Sketch cannot copy:
These moves cannot be sketched: Chatter, Mirror Move, Sleep Talk, Struggle, Sketch itself, Shadow moves, Z-Moves, and others depending on the generation. Sketch can copy Selfdestruct and Explosion only when a Pokémon with the Damp Ability is present.
These moves sketch can copy but Smeargle can’t use:
Although they can be sketched, Hyperspace Fury and Dark Void are unable to be used in battle since Generation VII. These moves can only be used by Hoopa Unbound or Darkrai respectively, or by a Pokémon that has transformed into them.
Sketch cannot copy Transform, Mimic, or Metronome in Gen 2 and 3, but that was changed in Gen 4. Hope this helped!
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