Under the 501st Legion, the Imperial commandos were divided into slightly larger squads than the "pods" that operated under the Old Republic. Galaar Squad and Omega Squad were combined into the Imperial Squad 40.

Were there commandos in the 501st?

With the end of the Clone Wars immediately followed by the rise of the Galactic Empire in 19 BBY, the remaining commandos were transferred to the 501st Legion, an elite stormtrooper unit under the command of the Sith Lord Darth Vader.

Was the 501st Special Forces?

The 501st Special Forces were the elite branch of the 501st Legion. They had armor similar to the Clone Shock Troopers, albeit blue. They were used in special operations, such as sabotage of an enemy base or an ambush an enemy officer.