I started off with these two, as per the core. I decided to go with Physical Sharpedo instead of special after finishing the team due to having 3 special attackers and only 1 physical attacker later in development. Absol is your standard LO + SD Pokémon, though I added Iron Tail so fairies didn't cancel all the momentum from the sweep.
From here, I added Mesprit to serve as a Rocker, a U-Turner, and a healing wish-er in one slot, and I gave it a Colbur berry to help combat dark types, and Mesprit's relatively high bulk make it an excellent pivot. It also helps Magneton get in on Steel types, because who in their right mind is going to EQ something with Levitate?
Now, my team is massively weak to bug and doesn't have a stable Fairy switch-in either, so I needed a steel type as a switch for them, one that can also deal with Steel types. I chose Magneton due to it's trapping pressure on Steel types with Magnet Rise and HP fire. It's also a solid check to Bug and Fairy that dark fears.
Now my team begins having an issue with Fighting and only Mesprit to stop it. After looking at possible fighting resists, I decided to throw on Togetic due to being able to Defog and Heal bell as well, while also accomplishing something similar to Mesprit against steel types because nobody in their right minds would go for an EQ against a flying type.
Lastly, we have Mega Audino, which I put on the team in place of a Granbull I originally had due to Audino's better bulk and ability to clinch games with the powerful Calm Mind/Rest/Sleep Talk, while also being a ghost check, a fighting switch [only when mega], as well as an extra dark switch that isn't weak to knock off like Togetic or extremely frail.
And that's it. Enjoy!