Henry Cavill seemingly left the DCEU today over scheduling for a Shazam cameo. His manager is also The Rock's manager so the pieces may be coming together for why there was none of The Rock's Black Adam in the Shazam trailer.
Moving on to how DCEU moves on, use the Flash's solo Flashpoint movie to make Arrowverse's Superman as the new Supes and have Thomas Wayne either fake his death during the robbery (or not) and become Batman with Bruce alive and unaware either way.