Which Pokémon are exclusive to each version

From the Nintendo Support Forums, this same question was asked and this answer was chosen by the moderator as the best answer:

No. Nintendo 3DS games and systems are both region-locked, so a German copy of Pokémon Sun would only work on a Nintendo 3DS system from that same region. Similarly, a NTSC Nintendo 3DS system would only be able to play a Pokémon Sun game from the NTSC region.

Therefore, Pokemon Sun and Moon are region-locked and you will not be able to play a Chinese or Taiwanese copy on your Japanese 3DS.

For a map of the regions that Nintendo locks according to, see here.

You can't trade Pokémon to/from Pokémon Sun and Moon with any other games.

Eventually, however, you will be able to transfer Pokémon to Sun or Moon from ORAS, XY, BW, BW2, and the virtual console RBY versions.

See here:

Pokemon Sun and Moon are not compatible with the Generation 6 series of games: Pokemon X and Y; and Pokemon Omega Ruby and Alpha Sapphire. You won't be able to trade or battle between these games and Pokemon Sun and Moon, therefore you'll need a special app called the Pokemon Bank to transfer your Pokemon.

Transporting Pokemon into Sun and Moon from Pokemon White, White 2, Black, Black 2 and the Virtual Console games Pokemon Red, Blue, and Yellow is also possible with Poke Transporter, which comes bundled with Pokemon Bank.

However, Pokémon Bank and Poké Transporter won't be available for Pokémon Sun or Moon until January 2017.