According to Dual Pixels, a source of theirs called "Geno" claims to have information about the next duo of Pokemon games.
Geno says that these titles will be called "Plus and Minus" and has provided the site with a small wealth of information, like how the new region is going to be South East Asian-inspired, and how the new legendaries will be Psychic/Ground and Ghost/Fairy. Here's his report in full:
>GameFreak were one of the first development studios inside Nintendo to receive Alpha-Prototype hardware, now have been upgraded to the Beta-Prototype hardware above.
>Have a few areas marked out, TONS of concept art traveling between Pokemon Company and Nintendo Co Ltd.
>GameFreak plans to completely overhaul the basic systems of battle, simplifying the process.
>The development team is “going to put a lot of ideas they have wanted to do for years in this game”.
>Two versions already have code names, possibly final: Pokemon Plus and Pokemon Minus.
>Theme is “Old Tradition VS New Exploration”
>New region, no name yet, is based on South East Asia with one large peninsula and many smaller islands.
>Three new starters with no names: Water evolves into Water/Steel and is a squat, teardrop shaped humanoid that has a jar filled with on its head as it evolves it grows taller and the jar bigger until it needs another set of arms to hold it on it’s head. Fire evolves into Fire/Fairy and is a tiny cute goat with fire blowing out of its horns, it’s horns and look evolves more menacing until it has curly ram like horns and a motorcycle hot-rod-like look. Grass evolves into a Grass/Electric and starts with a leap for a face with a nubby root as a body and evolves until it grows into an electric producing palm tree with each flower petal having a different face.
>The main legendary for Pokemon Plus is a Shi Foo Lion-looking Psychic/Ground-type that has multiple faces, the Pokemon Minus legendary is a Ghost/Fairy type that has two dashes for eyes and is a hurricane-like appendages with many arms and hands.
>More traditional Pokemon-like gameplay will be on the Handheld controller while an all new gameplay aspect will be on the Terminal unit.
>The “Pokken Fighers” render that was teased was running on Alpha kits, Beta kits now have advance cell shading. Going for very detailed “living anime” look.
>The new “Team” villains are described as a bunch of “Sohei Zelots”-types who have discovered the player’s best friend as a reincarnation of a special type of person who only is alive every 100 years. They believe the old system where people were given a Pokemon egg and they stick to that Pokemon until they die and who’s function in society dictate what role that person is. They are against the “modern” trend of Pokemon Trainers and capturing multiple Pokemon and are making a holy pilgrimage to evoke the old Legendaries to turn everything back to normal. They keep the player away from their friend, saying the special one (who can do amazing things like mega evolve Pokemon without the use of a mega ring) only love is that of Pokemon and not people. It is planned to be reveal later that for the special one to fulfill their role in society they must be mortally sacrificed to awaken the legendaries.
>Routes connection the island together are water bridges but clumps of island are connected together by underwater tunnels.
>There is a “Stone Slowking” statue that is a parody of the Reclining Buddha at Wat Pho, Thailand.
>Many Pokemon from Hoenn and Sinnoh will make a return.
>Variety of Pokemon Gyms, one is a mail system that only uses flying types and focuses on sky battles. One only uses baby Pokemon, one is implied to be a real vampire and uses Ghost and Dark Pokemon. There is also a military like leader who uses Fire and Steel Pokemon.
>The island gameplay with Gym Leaders and the Elite Four island can be played entirely on the Handheld and can be blown up on the Terminal for home play.
>New Pokemon Type similar to Shinies, no details yet on how they work but I’ve been told they “change the game significantly”.
>The “Mainland” is an MMO-like environment that is exclusive to the Terminal and is shared by both versions.
>Players all over the world online can chat, trade, intermingle and experience new-updated story lines on the mainland.
>Pokemon Band is a new mechanic introduced to get people involved who do not battle, a co-operative experience where Pokemon dance and make music together to achieve the highest group score.
>Pokemon Bank are actual locations on the Mainland and Handheld areas where people can import past Pokemon, mainly from Pokemon X and Pokemon Y into the new game.
Is this news trustworthy? Well, Dual Pixels claims that Geno has accurately leaked information about Castlevania: Mirror of Fate and the Kingdom Hearts HD Remix, so maybe. The stuff he talks about is certainly interesting (particularly those unusual starters) and the leaked X & Y legendaries (Hoopa and Volcanion in particular) do have a bit of a South East Asian look to them (possible foreshadowing?). It'd be interesting if that was the case. Until there's an official word from Nintendo, though, everything that he's mentioned is just a rumour.