Foxx voices the lead character Joe, a jazz musician and middle school band teacher. Details about Fey's character were not immediately available.
Daveed Diggs, Phylicia Rashad and Questlove have also joined the cast, Pixar said Saturday. The film will feature original music from Jon Batiste and a score from Trent Reznor and Atticus Ross.
Just Announced: @iamjamiefoxx and Tina Fey will lead the cast of #PixarSoul, coming to theaters June 19, 2020. Here’s a first look at their characters, Joe Gardner and 22, and a new piece of concept art. #D23Expo pic.twitter.com/vhK3GbAMwY— Disney D23 (@DisneyD23) August 24, 2019
The studio released three pieces of imagery related to the film during D23 on Saturday: a piece of concept art and two images showing Foxx and Fey's characters.
It was previously announced that Oscar winner Pete Docter would direct the film and Oscar nominee Dana Murray had signed on to produce. "Soul" imagines that every human attends a pre-birth seminar where they're given quirks and passions, Docter said Saturday.
Pixar had previously said little about the plot of "Soul," though the studio did drop a few hints when it announced the film's June 19, 2020, release date earlier this summer: "Ever wonder where dreams come from? What about your passions, or your interests? What is it that makes you, YOU? Well, next year, Pixar Animation Studios will take you on a journey from the streets of New York City to the cosmic realms to discover the answers to all of life's most important questions..."
VIDEOS: Trailers released during Disney's D23 Expo
The Walt Disney Company is the parent company of Pixar and this station.
The Associated Press contributed to this report.