Hello, I'm an expert in the field of Pokémon, and I'd be happy to help you with your question about Smeargle and its ability to transform.

Smeargle is a unique Pokémon with the ability Mimic, which allows it to copy the move of another Pokémon when it battles against it. However, this is not the same as transforming.
Transform is a move that allows a Pokémon to take on the appearance and move set of another Pokémon, but Smeargle does not have this move in its natural move pool.

In the Pokémon games, Smeargle can learn a variety of moves through TMs (Technical Machines) and HMs (Hidden Machines), but Transform is not one of them. It can, however, use Sketch, a move that allows it to permanently copy a single move from another Pokémon it has seen, provided that the move is not a Hidden Ability, nor a move that Smeargle cannot learn.

So, to answer your question, Smeargle cannot Transform, but it can use Sketch to copy a move from another Pokémon.

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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 >>