This was an April Fool's joke. The font and the mistakes in Japanese indicate it's a fake made by a non-Japanese fan. I apologize for having been trolled.
According to Weekly Shonen Sunday, a joint special anime of Detective Conan
and Kindaichi Shounen no Jikenbo
was announced. A collaboration adventure game of the two series was released in 2009 on Nintendo DS.
Detective Conan & Kindaichi game official website
Source: Scan of WSS