Natsume just announced via this cool lil' trailer.
YouTube
So, Rising Star Games just confirmed the game will be localised!
Source
Not to be confused with Story of Season (published by Marvelous/XSEED).
YouTube
Global videogames publishers Bergsala Lightweight and Natsume Inc today announces a new publishing deal for Harvest Moon: The Lost Valley, the latest game in the Harvest Moon series. This partnership means that Harvest Moon: The Lost Valley will be released across PAL territories in Q1 2015, exclusively for the Nintendo 3DS.
So, Rising Star Games just confirmed the game will be localised!
English, French, German, Spanish <3
Source
Not to be confused with Story of Season (published by Marvelous/XSEED).