The Academy Award-winning Barba (Best Achievement in Visual Effects, The Curious Case of Benjamin Button) also worked on Fincher's Zodiac, The Girl With the Dragon Tattoo, and Gone Girl.
Barba also served as Visual Effects Supervisor on Oblivion (from Tron: Legacy director Joseph Kosinski) and firefighter drama Only the Brave.
The World War Z sequel reunites frequent collaborators Pitt and Fincher, who teamed for Se7en, Fight Club, and Benjamin Button.
World War Z 2 is Fincher's first foray into big-budget franchise installments since 1992's oft-maligned Alien 3, which has been disowned by the twice Oscar-nominated director.
Fincher took over from J.A. Bayona in April, after the A Monster Calls filmmaker departed the zombie thriller early on in favor of helming Universal's upcoming Jurassic World sequel.
"We’re trying. A lot of stones have been laid," Fincher said of WWZ2's progress last month. "We’re just deconstructing it right now against the mythology that exists to see where we can go."
“We’re hoping to get a piece of material that’s a reason to make a movie, not an excuse to make a movie,” Fincher said earlier this year about the followup to World War Z, which earned Paramount $540 million worldwide in summer 2013.
World War Z 2 will be at least partially inspired by Max Brooks' World War Z: An Oral History of the Zombie War and is tentatively scheduled for a 2018 production start.