Breakdown’s alt-mode is almost identical to the silhouette of Animated and ROTF Lockdown’s: a caricature of a mean bruiser sort of muscle car. Although the vehicle modes do have some differences, over-all, this is how one could expect a War For Cybertron version of Lockdown to look.
With last week’s announcement of Demolisher joining the cast of War For Cybertron, all other Transformers storylines and characters are literally up for grabs to join the fight. Since Lockdown appears to be one of a handful of new generation characters to cross-over into multiple storylines, it is definitely plausible to see him appear as some sort of repaint version of Breakdown. Perhaps he is an un-lockable characters, or another part of the DLC.
Or maybe he isn’t in there at all and I am just grabbing at straws. Who knows, but I’ve got my TF sleuth nose to the ground from here on out until the game’s release later this Summer!