Billy Batson is the new Shazam, and subsequently, locked up in the Rock of Eternity. He monitors mystical disturbances around the world, but spends most of his time as a bored Billy Batson (who later takes on to exploring the non-Euclidian Rock).
Mary Marvel is the new Captain Marvel, maybe with a new pantheon, and she fights around Fawcett City, which has stayed all Norman Rockwell and has suitable magic weirdness surrounding it, 'cuz of the Rock of Eternity.
Freddie Freeman is, uuhh, something else? He's still crippled, but he can commune with the Six Mythic Cities of the Modern Gods (Silicon Valley, Hollywood, Atlantis(?), Zion, something else (Atlantic City?), and Metropolis (Fritz Lang's Metropolis, not Superman's Metropolis). Here he can walk free.