The Outsiders aren't to well known to non comic book fans. But they are the perfect team for a TV show and heres why.
The characters fit the Arrow universe perfectly
If they did a spin off the characters would fit in perfectly. Here is who I would put on the show and how to work them into the Arrow universe.
Katana is and Assassin from Japan. She is the easiest to fit in considering she is already set to be in Arrow season 3. I'm not sure how her origin story will be in Arrow but I am sure that she could spin off and help create a new team of heroes.
Black Lightning can generate electricity from his body. He would be good to bring onto the Flash. I would change his origin a little. Having him be around 22 in Central City for a Decathlon while the Particle Accelerator blew up giving him his electric powers. After finding out that he has powers he helps out the Flash then returns to Suicide Slums to help his people.
Geo-Force can manipulate gravity. He would work perfectly if the Titans tv show is also connected to Arrow and you tweak his origin a little. Having Geo-Force and his sister Terra be A.R.G.U.S. experiments later getting saved by the Green Arrow. Him and his sister later go back to A.R.G.U.S. to get revenge. While there they cause so much damage that Deathstroke is released from his cell. Geo-Force and Terra get separated and Terra freaks out because she can't control her powers. As Deathstroke is escaping he see Terra and he starts talking to her. Eventually getting her to come with him so he can help her. Green Arrow shows up and talks some sense into Geo-Force. Geo-Force realizes that his sister is missing and goes looking for her. Terra and Deathstroke would eventually go into the Titans show.
Metamorpho is made up of different elements and can shape shift parts of his body into different things. He could come in on the premiere episode of The Outsiders.
Jack Ryder can transform into the Creeper whenever he wants which allows him accelerated healing, enhanced human abilities, and a pain inducing laugh. He should appear as a cameo as a newscaster in Arrow. Then he should appear in the premiere of The Outsiders show.
Bringing them Together
Bringing them together would be easy. What I would do is bring them together on the first episode. It would start off with Rex Mason (Metamorpho) working as a guide for Vandal Savage in Egypt to help him find the Orb of Ra. Vandal has a team of people to help which consist of Deathstroke, Terra, Java, and Rex. The legend says not to touch the Orb of Ra with your bare skin because it is so powerful. After they find the Orb of Ra in the pyramid of Ahk-Ton, Rex realizes thats Vandal wants the Orb for bad reasons so he knocks it out of Vandals hands and Java starts attacking him. He picks up the Orb with his bare hands and knocks down Java with it. Deathstroke shoots Rex in the chest. Rex drops the Orb and Vandal picks it up. They walk out and Vandal tells Terra to tare the pyramid down.
Meanwhile Geo-Force is in Egypt looking for Terra he meets a man that had seen them and the man tells him where they went. He goes to the pyramid and sees it in shambles. He looks around to see what happened and finds Rex still alive. Rex tells him the direction Vandal went. Geo-Force put Rex in the car and they start driving in that direction. As Vandal and his gang are on their way to leave they run into Katana. Who is their to assassinate Vandal Savage. She ends up getting into a fight with Deathstroke, Terra, and Java and gets hurt badly. Vandal and them then continue on their way. Geo-Force and Rex then see Katana on the side of the rope and help her out. They leave to a safe location because Rex is started to transform into Metamorpho. After his transformation the three of them talk about what Vandals plans could be and they decide that they should try to stop him and take the Orb of Ra back.
Meanwhile in Metropolis a reporter named Jack Ryder(Creeper) is at an interview with Dr.Yatz about a new chemical that could make a person heal. Soon a group of thugs arrive from Suicide Slums. Dr.Yatz gets shot and tells Jack to do whatever it takes to stop them from getting the formula. Jack runs but hits a dead end. The mobsters point their guns at Jack and tell him to hand it over. Jack injects the formula in him and they shoot him. They leave him there dead. A couple of hours later he wakes up as the Creeper and goes to kill the mobsters. While he is out killing them he runs into Black Lightning and the two start fighting. The Creeper gets away and turns back into Jack.
A couple days later Vandal and his group head to Suicide Slums to take their plan of turning the Orb of Ra into weapons. They are followed by Katana, Geo-Force, and Metamorpho. The Creeper goes back out to kill more of the mobsters and him and Black Lightning start fighting again. Vandal gets the weapons up and running and starts to destroy the city with him army of thugs. Black Lightning and the Creeper come together and start attacking the thugs. Soon Katana, Geo-Force, and Metamorpho join them. They all take down the thugs and destroy the weapons but not before Vandal and his group can get away. They all decide to stick together Metamorpho suggest that they call themselves the Outsiders. Later in the series they could add in more characters like Freight Train, Halo, Looker, Red Robin, Arsenal, Terra, Huntress, Martian Manhunter, Indigo, Shift, Windfall, Jade, and maybe even Batman.