Its called a torque rod, its a cheap way to help a car hook up when you drop the clutch hard under power, it also reduces load on the motor mount rubber during aggressive shifting. It can also help eliminate the shudder from a hot clutch. Or make you really feel it if its bad
I install them on FWD cars all the time to help them pull smoother out of a turn at the track. Many FWD cars have really spongy motor mounts.
Dave