The main difference from Doubles OU is the limitation to only 4 pokemon in a team and the further limitation of only being able to use 2 of them, and that there is no switching. These are simple changes that can have a massive impact on how the battles are played and what the metagame is about. For example you cant force an opposing pokemon out by moves such as Whirlwind as a counter-play to setup and you can't switch out if your pokemon has been debuffed and statused.
Mechanic: Bring 4 Pokemon at Team Preview, pick 2 to battle.
Clauses: DOU clauses
Bans: DOU banlist + Perish Song + Tapu Lele.
2v2 Doubles is a metagame rich with strategies as you can easily abuse many aspects of the metagame such as terrains, weather, Trick Room and more. You can even choose not using any of that! Furthermore, mind games are an essential part of the game if you have played 1v1 the concept is fairly similar as you try to predict what your opponent might send and adjust your choices following that prediction. Here are few cores that you might see in the metagame.
-Viability Rankings [Coming Soon]
-Cores [Coming Soon]
-Sample Teams [Coming Soon]