Its kinda just become a thing over the years that with every new Pokémon generation comes a new gimmick or concept to change up the gameplay. It can be concepts as "simple" as double battles to something as dramatic as Mega Evolution. I think it would be fun to workshop something for our region. If ever we make a cool fangame out of it, it should help it stand out. So post your ideas bellow! No matter how wacky or crazy they may seem, it should be fun to workshop somethings together.
If I really have to suggest one. How about fusion moves? I know it would be ridiculous and very hard to code but it would be a great idea. Fusion moves are like the pledge moves where you can fuse two moves together to create one massive damaging moves. However, if every moves needs to be waited for the partner's move, a battle of 2v2 will become long winded. So, to make it a bit quicker, instead of searching and waiting for two moves with good compatibility, the fusion moves can be used at anytime during a double battle but can only used up to X times a battle(where X is a non-zero positive number) Here are some suggestions: Powder moves(expect rage powder)/spore + tailwind = The Powder moves(expect rage powder)/spore changes from single target into multi-target but with less accuracy Brine + any non-contacting non-status single target electric moves = Brine that also deal electric damage and can cause paralysis Muddy water + Surf = Stronger damage Surf with a chance of accuracy drop and does not hit the partner Pokémon(But this also won't trigger any ability or items though) Aqua ring + Life dew = Aqua ting but with stronger (The Life dew heal wont trigger though) etc. Of course, it is just a concept and well may be fun and may be just overpowered. Who knows.