There is not a place to do repeatable double battles. However, you can SOS chain Smeargle to have them learn moves. I wrote this on an answer to a similar question, but it applies here too. Replace "Fleur Cannon" with any move you want to learn, and "Magearna" with any Pokémon that knows that move.
First, you have to find a Smeargle in the wild. Use False Swipe, which the Smeargle will then Sketch, and an Adrenaline Orb. Switch to Magearna. Wait until Smeargle calls an ally, then KO the first Smeargle with Fleur Cannon. The ally Smeargle will then use Sketch and learn Fleur Cannon. Switch out Magearna and False Swipe/Paralyze the Smeargle (paralysis stops it from calling for help.) Once it has stopped calling allies, catch it. Et voila! Fleur Cannon Smeargle!
If you need more information, let me know!
