These are the Beta Elements for Mario & Luigi: Alternate Quest.
The orignal name was Mario & Luigi: Virtual Dimensions. However, Alternate Quest became the final name. However, in other countries then North America, it was still named Virtual Dimensions.
Roseleta from Mario & Luigi: The Cosmic Duo was orignally going to be playable, but was scrapped because of the ending. However, her Galaxy Destroyer is in the game as a cameo when Bowser gets sent there.
Early Bosses:Princess Shroongi was going to be a boss but was scrapped. Her sprite is still found in the game though.
Alternate Quest was in development during 2012. Hacking the artwork page shows you theres a unused artwork of Princess Shamrock, that was also seen on early pages.