According to a tweet by Nintendo of Europe, Pokémon Black 2 & White 2 will be released in Europe on October 12th. Along with B2/W2, Pokémon Dream Radar (and although not mentioned, it’s safe to assume that Pokédex 3D Pro is included in the mix) will also be released on the same day.
As far as North America goes, the official B2/W2 website has October 7th as the release date. The official site also reveals the English names of your rival and Shizui. The rival’s default name is Hugh, while the Water-type Gym Leader will be known as Marlon. Finally, PokéWood has been translated as Pokéstar Studios.
Added new English trailer that showcases the above information.
Achroma’s English name is Colress.