Is Chaos;Child coming back?

No — Chaos;Child ended on March 29, 2017, after its first season aired on AT-X. The series was a science-fiction and mystery anime set in October 2015, six years after the events of ChäoS;HEAd. It focused on abnormal events that began to occur in the Shibuya district, including mysterious deaths, and followed the story of Takuru Miyashiro and other characters as they unraveled the strange occurrences. The show featured a cast including Yoshitsugu Matsuoka as Takuru Miyashiro, Sumire Uesaka as Serika Onoe, and Inori Minase as Uki Yamazoe. It aired a total of 12 episodes, each approximately 25 minutes long, and was part of the 2017 anime lineup.