STV Ep. 0 was just supposed to be a very silly introduction to the main female lead of STV, to sort of build up hype for the franchise's NYC "restart." It plays absolutely nothing like any of the other ST games.
It's supposed to have a lot of references to previous ST stuff...for example, one of the main bad guys in Ep. 0 was one of the bad guys from the ST movie, the enemy mechas were built by an American corporation to replace the Tokyo Hanagumi in the ST movie, etc.