Justice League Dark is a movie that has been in development hell for what feels like half a lifetime. After losing Guillermo del Toro they found a second director in the form of Doug Liman. However, he recently had to leave the project due to scheduling conflicts. Wanrner Bros has been actively searching for a replacement and we've already heard rumors about IT director Andres Muschietti was on the list to replace Liman.
On Meet the Movie Press host Jeff Sneider added another name; Damián Szifron. If you've never heard of Szifron that isn't that surprising since he hasn't made a Hollywood feature yet. He's mostly known in his home country of Argentina and for his movie Wild Tales. However, Sneider also clarified that while Szifron is being added to the list Muschietti likely has a better chance at getting the job since he has a connection to Warner Bros through IT.
Both of these directors are interesting choices to even have their names out there and perhaps it points to DC/WB taking a different direction with their projects. At the moment most of the directors for DCEU have been big, established names so it could be fun to see some very fresh blood in the group. Either Muschietti or Szifron would likely give 110% and then some if they were chosen because movies like this make or break big Hollywood careers.
We should be learning more about what plans DC has for its movies post Aquaman in the coming months. Perhaps we'll see some sort of announcement in Hall H at Comic-Con International in July.