Agatha All Along introduced a prime replacement for Kang the Conqueror, one whose power levels more than rival those of Thanos in the MCU’s Infinity Saga. Full of dark magic and major twists as Agatha and a group of fellow witches went down the Witches’ Road, the MCU debuted one of the most powerful beings in the Marvel Universe. As such, it’s quite possible that she could become an ongoing antagonist as the current Multiverse Saga continues.

https://screenrant.com/agatha-all-along-mcu-kang-replacement-thanos/