Black Widow is based off a Marvel superhero of the same name. Although I am not entirely sure which version inspired this look, I am 90% sure it was from the Avengers movie. Her secret identity is Natasha Romanova. Romanova has a gifted intellect. She displays an uncanny affinity for psychilogical manipulation and can mask her real emotions perfectly. The Black Widow is a world class athlete, gymnast, acrobat, aerialist capable of numerous complex maneuvers and feats, expert martial artist, marksman and weapons specialist as well as having extensive espionage training. She is also an accomplished ballerina. Romanova is an expert tactician. She is a very effective strategist, tactician, and field commander. She usually wears distinctively shaped bracelets which fire the Widow's Bite electro-static energy blasts that can deliver charges up to 30,000 volts, as well as "Widow's Line" grappling hooks, tear gas pellets, and a new element introduced during her ongoing series during the "Kiss or Kill" arc called the "Widow's Kiss"—an aerosol instant knock-out gas she has modified.
Hawkeye is based of a Marvel superhero of the same name. His design too come from the Avengers movie I think. His secret identity is Clint Barton. He is at the very peak of human conditioning. He is an exceptional fencer, acrobat and marksman. Hawkeye has also been thoroughly trained by Captain America in tactics, martial arts, and hand-to-hand combat. Hawkeye excels in the use of ranged weapons, especially the bow and arrow, and carries a quiver containing a number of customized "trick arrows". He has gained a reputation for being able to "turn any object into a weapon", and has been seen using items such as tin plates, coins, sticks and other debris to great effect against his enemies. Hawkeye is also known to use a "Sky-Cycle" as his mode of transportation. The Sky-Cycle is modelled after a commercial snowmobile and is fitted with anti-gravitational technology. It is voice-operated and has an auto-pilot steering system.