In the comics, The Knights Program, which became known as the Gotham Knights, was an initiative to create a stricter version of the Batfamily, including Batman, Batwoman, Robin, and others. There’s also a video game of the same name releasing October 5, including Nightwing/Dick Grayson, Red Hood/Jason Todd, Batgirl/Barbara Gordon, and Robin/Tim Drake (according to the website), but this project is unrelated.
Set after Batman’s death, the CW version of Gotham Knights will see Bruce Wayne’s rebellious adopted son forming alliances with former cronies of the Caped Crusader and the children of some of his most notorious villains. The group will work to clear their names after they’re framed for the murder of Dark Knight himself (via EW).
Essentially, while the series borrows the idea of Batman-related characters coming together in a team called the Gotham Knights and a Batman-less Gotham City storyline, this feels like a totally original introduction to both the Batman mythos and the expanded DCTV universe.