From the Scarlet Witch to Franklin Richards, Agatha Harkness has a way of finding herself mentoring the greatest powers on Earth. As revealed in 2020's Captain America #19 by Ta-Nehisi Coates, Jason Masters, Bob Quinn and Lucas Werneck, she also moonlights as a teacher for a secret society of warrior women.
After finding Steve Rogers on the run, Agatha explained to Steve the history of the mysterious organization known as the Daughters of Liberty. Her explanation confirmed Captain America's suspicions that the group was older than anyone suspected. Agatha's role in training Agent Peggy Carter and the other secret defenders is just another link in her long chain of training or protecting the great powers that inhabit the Marvel Universe.
Agatha Harkness first debuted in Fantastic Four #94 by Stan Lee, Jack Kirby and Sam Rosen as the governess for the newly born Franklin Richards. But their first meeting quickly went awry when the Frightful Four attacked. They incapacitated the FF and planned to kidnap Franklin. The only one left standing in their way was Agatha, who quickly defeated each of them with her mystical might. When the Fantastic Four finally came to, they found Agatha gently rocking Franklin and hinting that she is a real-life witch.
Agatha is purportedly old enough to recall just 500 years before Atlantis sank into the sea, which is estimated to have occurred over 12,000 ago. If true, this makes Agatha one of the oldest beings on Earth, as well as a witness to a great many events in the long history of the Marvel Universe, such as the coming of beings like Apocalypse. So when one considers her knowledge of the past and how beings with great power can turn if left unguided in a fearful world, it's no wonder she takes such an active role in training the future powerhouses of the Marvel Universe.
While Franklin Richards is certainly at the top of the list of the most powerful people she has cared for, Agatha has also helped others whose powers are not cosmic in nature. One of her more famous disciples is the Scarlet Witch. Agatha began training Wanda Maximoff in true witchcraft, further adding to her prodigious collection of prodigies. Years later, the two eventually fell out, but Agatha was never the purest heroine either.
And now, she has also been revealed as having trained the Daughters of Liberty. This is a secret cabal of women who trained in combat, science and sorcery to protect the world from men who abuse the great innovations humanity had developed over the years. While the exact date of when the Daughters were officially found is open to interpretation, the style of clothing they wore during their initial formation indicates it's sometime within the last half a millennium. So naturally, any secret society of women that included sorcery would want to go to Agatha as a source of knowledge.
And Agatha agreed to train them. It is unknown how many of the Daughters she trained, but it can be assumed that it was a majority, if not all of them. The most prominent of these Daughters was Agent Peggy Carter, whom Agatha had a hand in training in some mystical arts. This allowed Peggy to survive into the present day to keep a watchful eye over the world and prevent the return of old threats.
However, her presence on the Daughters of Liberty means that Agatha doesn't just watch over those with great power, she also strives to empower those without.