Some stuff form the fanfiction archives to get a feel for this. http://www.fanfiction.net/Star_Fox_and_Metroid_Crossovers/385/542/
Descriptions include:
"Samus and Krystal are forced to join forces to eradicate a new Space Pirate super-weapon"
"What are the consequences for the universe now that Samus has the Triforce?"
and "this was something i made at12:00 a.m."
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Smurf, the cream of Sonic fanboyism