They have announced the first batch of artists that will be involved in the album and they are...
Bakusho Mondai's Ota Hikari (OMG he will be the lyricist for one song with music provided by Hisaishi Joe.)
Love Psychedelico (This is the first time they are composing music for other artists.)
Makihara Noriyuki (Composer for "Sekai ni Hitotsu dake no Hana")
Apparently there might be other artists that will be contributing too according to the news.
I wonder if BEP will be involved this time too.