You need to find Sableye to complete your Pokédex, which is a hefty challenge to do in Pokémon Sword and Shield. Unfortunately, those with Sword are going to have a bit more difficulty in acquiring this Pokémon because it’s only available in Shield. A Shield player needs to trade it to them to complete their Pokédex, so this next portion of where it spawns and how to get it is solely for Shield owners.
The only location Shield players can find a Sableye is in the Dusty Bowl in the Wild Area. However, the problem is a Sableye only shows up in this location when there’s Heavy Fog. Making fog appear is extremely difficult, but you can reliably have it spawn after you’ve gone through and beaten the game. To beat the game, you need to enter the Hall of Fame and defeat Leon.
If you haven’t done this yet, you won’t have an opportunity to capture a Sableye. When the Heavy Fog does arrive, you have roughly a 35 percent chance of seeing a Sableye in the overworld, which means you can see it walking around in the game. It can spawn anywhere from level 42 to 47.
To reliably have the Heavy Fog show, you can go into your Switch’s main settings and change the time of day. You want to switch the calendar date to 06/01/2020, which players have discovered is the best way to have Heavy Fog show up throughout the entire game.
Anyone who wants to help a Sword player out and trade them a Sableye needs to have access to Nintendo’s Online service. Go into the Y-comm function, and go down to Link Trade option, and then choose Set Link Code. Create a quick four numbers for the password, and give it to your friend who you can then trade a spare Sableye so they can add the Pokémon to their collection.