Lets share any new gameplay mechanics we can think of that would be interesting. Doesn't have to be related solely to battle, could be something fun on the side like Contests, Amie, Pokeathlon etc.

I'll start with mine: Bond Moves.
Whilst in a double or triple battle, Pokemon may learn the moves of their allies.Each Pokemon can only learn up to 4 Bond Moves (if they are forgotten, they can be relearnt from the Move Relearner). For a Pokemon to learn an ally’s move, both Pokemon must share an egg group. When Pokemon 1 uses the same move on multiple occasions, Pokemon 2 will begin to learn that move. Each move has a specific number of times it must be used to be learnt by another Pokemon, and the learning process typically spans across numerous battles- weaker moves are learnt more quickly, while stronger moves take more time. If, when the move is used, it defeats an opponent, it will count as 2 uses.

This technique allows for Pokemon to learn moves they could not normally learn, and gives pretty much every Pokemon more coverage options. Each Pokemon has a specific set of moves they are able to learn through this mechanic- for example, when it comes to Fighting type moves, Pikachu is only able to learn a few (Bulk Up, Brick Break, Vacuum Wave), and is unable to learn any Poison type moves. To keep a semblance of balance, stronger Pokemon would not get some of the more powerful moves they don’t already have access to (no Garchomp with Ice Hammer, Tapu Koko with Flare Blitz, etc).

This mechanic can also be used for new evolutions- for example, having Eevee learn a Fighting move as a Bond Move could enable it to evolve into a new Fighting Eeveelution.

So, thoughts? Yay or nay? I'd like to see other ideas you guys may have.