Agatha All Along: The Witches' Road explained
It's all thanks to the comic history of the Witches' Road, which first appeared in 2016's Scarlet Witch #3 by writer James Robinson, artist Steve Dillon, and artist Chris Visions (the first artist to depict the Witches' Road itself). In that story, Wanda Maximoff travels to Ireland to help lift a curse that is blighting the land.