In the finale's first end-credits scene, Monica is pulled aside by a government agent who reveals herself to be a Skrull. She tells Monica that a friend of her mother heard she had been grounded and needs Monica in space. Monica, who was stationed in space before her mother fell ill and then disappeared in the blip, is visibly excited at the thought of returning "up there."
The Skrull refers to her mother's friend as a "he," so the friend is either Nick Fury or Talos, both of whom Maria met in Captain Marvel and probably kept in touch throughout her starting S.W.O.R.D. The most logical conclusion is that this leads to Monica's appearance in Captain Marvel 2. But it could also be a hint that Monica will appear in Secret Invasion! The upcoming Marvel series covers the Skrulls invasion of Earth, which we've seen glimpses of in Spider-Man: Far From Home and Captain Marvel.
