Young Justice is doing a better job in adapting various DC Comics characters than Black Lightning and in staying true to the original concepts of those characters. This is not to say that Black Lightning is a bad show, but that it's taking more liberties with its source material, which hasn't always proven beneficial.
Resurrected on DC Universe following an untimely cancellation on Cartoon Network, Young Justice has been highly praised for how it has adapted various DC Comics storylines and characters into a format more easily consumed by non-comics readers. Indeed, many of the show's storylines - such as an arc which saw Green Arrow's sidekick Speedy being fitted with a robot arm and becoming Arsenal - were better received than the comics that inspired them. Black Lightning made similar efforts to bring various characters to life in live-action, particularly in the second season as they brought in obscure villains from the Outsiders comics like The Masters of Disaster and Windfall.
In the comics, Windfall was a teenage girl named Wendy Jones who had the power to generate strong winds. Wendy only became a supervillain because of pressure from her evil older sister and she eventually joined the Outsiders and tried to turn her life around. Wendy joined the Young Justice cast in episode 15, "Leverage", as one of several juvenile delinquents with superpowers. She was given a chance at redemption through a mentoring program run by STAR Labs. Black Lightning's version of Windfall was an ordinary teenage girl named Wendy Hernandez, who developed wind-control powers after becoming a test subject for a government program to turn urban youths into metahuman super-soldiers.
Both shows also developed the character of Dr. Helga Jace in dramatically different ways. In the comics, Dr. Jace was the Royal Physician of the Markovian Royal Family and was responsible for awakening the metagenes of both Prince Brion and Princess Tara. Though originally a loyal member ally of the Outsiders, she was eventually outed as an agent of the Manhunters and betrayed the team. The Young Justice version of Dr. Jace has yet to betray the team, but it has been suggested that her loyalties lie elsewhere, even as she has acted as a medical adviser to the Outsiders and entered into a romantic relationship with Jefferson Pierce. No such relationship exists in the Black Lightning series, where Dr. Helga Jace was introduced during season 2 as an unethical medical doctor and geneticist, who was imprisoned for her illegal and immoral experiments.
The versions of these characters as presented in Young Justice are more compelling than their counterparts on Black Lightning. Wendy Jones, while rebellious at heart, showed a clear desire to take control of her life and her powers so that she could avoid having to be burdened with a power-control collar. Wendy Hernandez, on the other hand, was a virtual non-entity and existed primarily as a threat to be brought down or a victim to be rescued. A similar comparison could be made between the two versions of Dr. Jace, with the Young Justice version seeming more complex and conflicted, whereas the Black Lightning take on the character is a generic mad scientist with no real sense of emotional depth.