If it's Jason Todd, then I guess this Red Hood prevails here. While Revy is a deadly accurate shot with various firearms, much of her battle experience stems from her upbringing on the streets and she tends to be rather impulsive in battle, which can screw her over when battling more formidable foes like Roberta and Ginji. While Jason had a similar upbringing as Revy before being adopted by Bruce, he has received formal training in the martial arts and battle strategy/ tactics through Bruce and other masters through his worldly travels following his resurrection. His skills in the martial arts are such that he was capable of subduing the Titans team and giving Tim Drake, Bruce Wayne and Dick Grayson plenty of difficulty in their individual clashes with Jason and he was cunning enough as Red Hood to gain dominance over a good number of Gotham City's gangs. Considering the threats that Jason's put up with, he shouldn't have much trouble taking out Revy so long as he has a strategy planned to dispatch her.