I was pretty sure that there was a 2008 and 2009 Cobalt SS/TC Sedan, which only came in manual.
But yeah, the sedan was never supercharged from the factory, and the only other "SS" sedan was really the "Sport" model with the 2.4l N/A LE5 engine.
The easiest ways to tell if it's an SS/TC sedan are to look at the front bumper, check the engine bay for a turbo (duh), and see if it has the SS interior. Below are some photos of each:
Base Model Cobalt Front Bumper
Note the horizontal lines where there would be fog lights.
On models with fog lights, the horizontal lines are still present.
Cobalt SS/TC Front Bumper
Note the smooth contouring around the fog lights & the lip underneath the bumper.
Cobalt SS/TC Engine Bay
Note the word "turbo" on the valve cover and air pipe across the top of the engine to channel air to the intercooler.
Cobalt SS/TC Interior
Note the 2 tone seats that brandish the "SS" logo, and the boost gauge mounted to the A-Pillar.
In addition, the gauges have a higher maximum speed & different font and color than the base models.