Metroid: Federation at War for Forces of Corruption allows players to chose to play as either the Galactic Federation with Bounty Hunter Samus Aran and Commander Adam Malkovich or play as the Space Pirates with the Evil Phazon being Dark Samus and Geoform 187, Meta-Ridley.
Nice! I like the Federation picture. One thing we will need to determine is whether Federation HQ (Mentioned very frequently in Other M and Metroid Fusion) is related to the Assembly Hall on Daiban or if it is located on Earth. The games are very unclear. In fact, Other M almost seems to refer to Federation as a planet at one point. Maybe Federation HQ is another name for Daiban in the same way that Urtraghus was called Space Pirate Homeworld. More likely, HQ refers to the building, which brings me back to the first question.
Shoot! I'm wrong. According to Wikitroid, Metroid and Super Metroid described the Federation HQ as being located on Earth. The Assembly Hall on Daiban is separate.