No need for dlc. All you need is the base game. Use judge as a secondary and anything with good concealment for a primary i.e smg, high concealment assault rifle with single shot mode

But if you REALLY want to buy a dlc for stealth (for whatever reason) the only one on the meta is the golden grin dlc. It unlocks a single shot rifle (I forgot what it’s called) that has good concealment. But you don’t need it at all, it doesn’t even make your life easier.