As a Pokémon expert and enthusiast, I'm here to provide insights into the mechanics of Pokémon battles and abilities. Now, let's address your question about Smeargle and its ability to learn the move Transform using Sketch.

In the Pokémon games, Sketch is a move that allows a Pokémon to copy the move it sees an opponent use once. However, there are certain moves that Sketch cannot copy, and Transform is one of them.
Transform is a unique move that changes the user's form and type to match a target Pokémon, and it is not learnable through typical methods like Sketch.

Transform is a move that is often pre-set in a Pokémon's move list by the game, and it is not taught or learned in the same way other moves are. This is why Smeargle, despite its ability to learn a wide variety of moves through Sketch, cannot learn Transform.

To summarize, Smeargle cannot learn Transform using Sketch because Transform is not a move that can be copied by Sketch.

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I have successfully sketched Transform in a double battle. the Smeargle must know Dig, Dive, Fly, Bounce, or Shadow Force. Have Ditto transform into Smeargle and Smeargle use 2-turn move (Ditto must be slower (Lagging tail, anyone?). Transform will fail due to lack of target.read more >>