Sega announced their TGS lineup today with no big surprised. Persona 5 will be there, Phantasy Star Online 2, yadda yadda yadda, and... in the source code for the site, something called "Thirteen Mecha Soldier Defense Zone" for PS3, PS4 and Vita.
...which folks think might be the thing Vanillaware said they'd tell us more about in September.
People are also pointing to the yearly art Vanillaware put on their site back in 2013 as "the middle image has the Mecha name on it,"
but I seriously doubt this will have anything to do with the game. Vanillaware put up a piece of art every New Year's which never, ever bear any resemblance to the games they're working on.
Whatever this is, I'm hoping it's turn-based.
...still burnt we never got a localization of Grand Knights History. But whatever it'll probably be on Vita and that's all I need. Vanillaware + Vita = happy happy Chance happy happy.