Discharge

A Japanese only G1 Micromaster combiner limb, the extremely unfortunately named Discharge is a female fire engine. Her 2002 reissue bio reads:

"Contrary to her robust outward appearance, Discharge is a female Cybertron warrior. Few Cybertron fighters have seen her true appearance, as she is usually equipped in her heat-resistant armor. Devoting her passion to firefighting and rescue missions, Discharge really shines, no matter how she looks on the outside. She doesn't enjoy aggressively participating in battle, but she can be rather scary when angered."

Other than that, her main distinguishing feature is having one of the worst names ever, and certainly the worst for a female TF. Just eww...