https://screenrant.com/hawkeye-kate-bishop-antman-3-return-pym-arrows/

Ant-Man and the Wasp: Quantumania could feature an appearance by Kate Bishop (Hailee Steinfeld), and Hawkeye already set up how she can return.

From Wandavision to Hawkeye Disney+ has always thought to make Marvel characters the center of attention of the entire series and so when a series is finished it usually means in the show's last episode that a new storyline for the character will begin in a movie. As we saw with Wandavision showing a storyline for Wanda in Doctor Strange II Hawkeye already had a smart idea to make Kate the second most popular character in the show next to Hawkeye himself and with a spin-off series called Echo in development Marvel knows how to market their big hero stars well. I think why Hawkeye already knew that Kate would also have an appearence in Ant-Man 3 is because they hope Kate will be popular as she was with Hawkeye and gain more attention in Marvel characters. But Hawkeye will still remain popular as a Marvel character
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