WMG: Spider-Man: The Animated Series
Dr. Crawford's serum didn't entirely reverse the effects of James Reeves' formula on Kraven.
In "Duel of the Hunters", Kraven is able to smell two-year-old gunpowder on Man-Spider's hair, and also put up a decent fight against the Punisher despite not having any weapon other than one bola. Evidently, the antidote restored Sergei's rationality and reduced his strength somewhat, but he still had enhanced strength, reflexes, and senses.
If season 5 was made, Spider-Man and Black Cat would have discovered each other's secret identities.
Since Felicia/Black Cat was such an important and popular character, it's likely the writers would have brought her back for at least one episode, and where you find Black Cat, you find Morbius.