With Matt Reeves now officially attached to direct The Batman, it was assumed that part of that deal was to start over script wise to allow Reeves’ input. If that’s the case and with Joe Manganiello under contract or attached to play Deathstroke, it would be perfect to just switch him over to the Nightwing baddie.
This would allow Matt Reeves to find his The Batman story (maybe with a host of Rogue’s Gallery villains to include Jared Leto’s Joker). Besides who wouldn’t want either an adaption of The Judas Contract or lead up to a Titan film that would cover that story line. Cyborg is already introduced and Nightwing is now apart of the DCEU, all you would need is introduce the other Titans. Justice League Dark could introduce us to a cinematic Raven and Beast Boy, while Green Lantern standalone could bring Starfire to cinematic life or have her preexisting as Nightwing’s love interest in the Nightwing film. All of which lead to a Titans film. Titans Go!