Google has announced that they are holding a hardware event on October 15.  This event will showcase the new Pixel devices.  In the promotional photo for the event there seems to be a bit of Stadia tease with a Stadia controller.

 

 

In the top left of the picture is where the controller is. Could Stadia have a presence at the event?  Perhaps.  My gut feeling is that Stadia will be mentioned at the event and Stadia Pro will be given away with new Pixel devices.  This would be similar to what Apple is doing this year with their devices and Apple TV +.