you don't
No in emerald you can.
Sorry, you can't get Smeargle in Pokemon Leafgreen. All you can do is trade from one of the Hoenn games, like Sapphire, Ruby, or Emerald. :(
smeargle does not evolve
No, Smeargle is not a Legendary Pokémon.
well, apparently, your smeargle has to be paired with another smeargle of a different gender or a ditto. If you paired the smeargle with anything else it wont work.
Smeargle is a Normal type pokemon.
Enter a double-battle with smeargle and a Pokemon with spore. Have that Pokemon use spore and have smeargle use sketch on him/her.
You can find Smeargle in route 212 using the Poke Radar.
No, Smeargle does not have an evolution. It's a one-stage Pokemon, meaning it has no evolutions or pre-evolutions.
Smeargle can learn transform in two ways. In Gen III if you put ditto to sleep then have use transform it will fail, and smeargle can sketch it. In Gen IV onwards 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 (use the lagging tail). Transform will fail due to lack of target. next turn, have Smeargle use Sketch on Ditto, and give ditto a berry. Sketch will successfully copy Transform
It has no evolution.
RayquazaRare or Legendary? Legendary, the same in Ruby and Sapphire. Groudon, Kyogre, Rayquaza, Latios/Latias, the Regis. Not very many, rare pokemon,besides what you can get after the national dex, like sudowoodo, or smeargle.