Looking to catch a Minccino in Pokémon Sword & Shield? Well, look no further because you probably already caught it while reading this sentence. These things are absolutely everywhere, especially when it comes to the Wild Area.
Find The Little Gremlin
Yes, that's right, Minccino being the dressed up rat that it is, you're not going to have trouble finding it all over the Galar Region. The sole place that you're going to find it outside of the Wild Area is Route 5, where you'll have a 15% chance to encounter it in a non-overworld battle.
The Wild Area encounters for Minccino literally take up an entire book. You can find it in Rolling Fields during normal weather and while snowing as a non-overworld encounter, with higher odds in Sword than Shield, 35% to 5%, though those odds are the same in snow. You can find it at Giant's Cap (overworld) and East Lake Axwell (non-overworld) during virtually every type of weather at varying odds. It can be fought in Max Raid Battles at East Lake Axewell and Rolling Fields.
Its evolution, Cinccino, can be fought in Max Raid Battles at the same place, and can be found in Giant's Cap during normal, heavy fog, and overcast weather. You might want to go for this encounter due to Minccino's slightly annoying evolution method.
Evolution And Battle
In order to evolve Minccino into Cinccino, you'll need a Shiny Stone. This can be found on Route 8 by Doctor Joanna or near a rock formation in Lake of Outrage, though you'll need to have the water bike for the latter. The earliest you'll be able to find is on Route 8, so going with a Cinccino encounter over Minccino might be your best bet, but it's really up to you.
While Cinccino doesn't have any Gigantamax form after it evolves, it is still certainly a worthy member of your team. It's got some great speed to make use of, and moves like Tail Slap and Rock Blast will benefit you.