Marvel added Anthony Mackie to its superhero sequel “Captain America: The Winter Soldier” last month, and sources say the studio’s now focusing on casting the film’s female lead. Hollywood insiders tell us that current front-runners for the coveted role include “The Twilight Saga” star Anna Kendrick, as well as Felicity Jones, who reportedly lost out to Keira Knightley for the lead in Paramount’s untitled Jack Ryan reboot. Imogen Poots, who’s filming Terrence Malick’s “Knight of Cups,” is also in the running, we’re told. Joe and Anthony Russo are directing the “Captain America” sequel, and have hinted they’ll go with a “darker, edgier” tone for the film, which isn’t scheduled to hit theaters till 2014. Chris Evans is returning as the Captain, while Sebastian Stan is coming back as character Bucky Barnes from the first movie — but he’ll reportedly turn into a villain for “Winter Soldier.” Last year, “Captain America: The First Avenger” raked in $368 million worldwide before Evans took his character to Marvel’s even bigger “The Avengers.”