Hailee Steinfeld responded to questions about her participation in Avengers: Doomsday but did not confirm her return. She portrays Kate Bishop in Marvel productions; when asked about the film on The Tonight Show Starring Jimmy Fallon, she stated that she wasn't sure and that time would tell.
Her response and expression led some viewers to speculate that Kate would appear in the film. Marvel had previously released a cast list, but neither the current roster nor discussions surrounding new additions and returning characters could confirm whether Steinfeld is involved.
The trailer also features a brief scene interpreted as being related to Kate's residence. However, the identity of the character shown has not been confirmed, so this cannot be taken as definitive proof that Kate will appear in Avengers: Doomsday.