Henson will play Yess, a trend-aholic algorithm who acts like a guide to Ralph (John C Reilly) and Vanellope (Sarah Silverman).
The story sees the duo's game break down and require a replacement part, causing the characters to venture into the wild world of the Internet.
Silverman, along with directors Rich Moore (who won an Oscar earlier this year for 'Zootopia') and Phil Johnston, were onstage to present a clip of the movie.
As she interacts with them, she develops a respect for them and gives them a wardrobe change.
Many of the original voices of the princesses returned for the scene, including Jodi Benson (Ariel), Paige O'Hara (Belle), Linda Larkin (Jasmine), Irene Bedard (Pocahontas), Anika Noni Rose (Tiana), Mandy Moore (Rapunzel), Kelly Macdonald (Merida), Auli'i Cravalho (Moana) and Kristen Bell (Anna).
Produced by Oscar winner Clark Spencer, "Ralph Breaks the Internet: Wreck-It Ralph 2" is scheduled to release on November 21, 2018.