Hourman is a pretty deep-cut for DC, though that has never stopped successful superhero or movie franchises before. Guardians of the Galaxy and The Jump Street movies come to mind as films that shocked audiences and critics alike in the sheer surprise of just how great those movies were.
The character of Hourman has been portrayed mostly through comics since his first appearance in Adventure Comics #48, where he was the cover character. Aside from brief stints on Legends of Tomorrow, Stargirl, as well as a few appearances in animated movies, Hourman is a largely unknown superhero for the many decades he has been around.
Little is known about this plot and, in fact, which iteration of the hero the film will follow. Typically, Hourman is one of three men Rex Tyler, Rick Tyler, or Matthew Tyler. Hourman, being one of the earlier superheroes, has similar powers to the early typical super powered being. Super strength, speed, and durability, though typically Hourman takes a pill to give him those powers for an hour. However, it would not be a surprise if they change the origins or even powers of the character.
Hourman, while unknown right now, has the potential to be an intriguing take on the superhero genre. Long before James Gunn came around, characters like Groot and Rocket Raccoon were unknown to the general movie-audience, but now nearly seven years later, those characters are main stays in popular culture.
The point being, if James and Widener have an incredible script, the director has a passion for the character, the actor playing the character is perfect, Hourman could be the next Batman, Iron Man, or Hellboy. However, only time and a passion for the project will tell that.
There is no set production or release date for Hourman.