Guaranteed Double Battle?

I’m looking to train a Smeargle to be the perfect catching pokemon so to make that easier I was wondering if there is any spots with a guaranteed low level double battle so I can Sketch properly?

I’m pretty sure all random battles have a chance of being a double battle, whether in the wild or in a friend safari. However, the chance seems to be pretty low, so you’d just have to get lucky.

All areas have a chance to have Wild Double Battles. You should probably try to do it in your Secret Base as it is the most convenient place to do it.