apparently, flumpool makes a chinese version of Akashi and the translation is made by mayday's vocalist and vice versa, flumpool translates one of mayday's song called OAOA from chinese into japanese.
the video below is the collaboration concert between flumpool and mayday and for the encore they both sing chinese version of Akashi and japanese version of OAOA together.
and this is the MV of chinese version of Akashi by flumpool:
personally, i like the chinese akashi MV better than the japanese version though both are good.
and last week, i found a news that they do another collaboration by singing the soundtrack of the new movie of Oshin together, the song title is Belief ~Haru Wo Matsu Kimi E~ and it's another great ballad that sounds so flumpool-ish :P
here is the youtube MV:
i'm looking forward for another collaboration (concert maybe) in the near future :D