The copyright for Aliens vs. Predator is owned by 20th Century Fox Studios.

The copyright for Stargate: SG-1 is owned by Metro-Goldwyn-Mayer Inc.

The copyright for Mighty Morphin’ Power Rangers is owned by Haim Saban.

The copyright for Teenage Mutant Ninja Turtles is owned by Viacom.

These copyrights, to the best of my knowledge, are accurate, and certainly I do not here claim ownership of any of the above franchises, only for the idea of the Crossoverse, which combines them in a unique setting.