Director Ruben Flesicher confirmed the symbiote Riot will appear in Venom, and there may be more villains to come in the Sony Marvel film.
During the San Diego Comic-Con Hall H Sony panel this year, new footage showcased another symbiote in the mix for the film. Fleischer confirmed on the panel that this is indeed the symbiote Riot, one of The Five Symbiotes. According to IGN editors who saw the footage, the footage also possible teased the symbiote Scream, as a yellow symbiote was also seen. The identity was not confirmed, however.
As for further confirmation, Fleischer did confirm that Michelle Williams is playing Anne Weying following previous reports, who is Eddie Brock’s (Tom Hardy) ex-girlfriend in the film. This is a slight alteration of the comic, as Anne is Eddie’s ex-wife there. In the comics, Anne also takes on the identity of She-Venom, however no mention of that particular symbiote was made at the panel.
Source: IGN.com New Venom Footage Teases More Symbiotes