Name of movie with a killer that comes back after a death sentence and kills through outlets and travels through powerlines its not THE SHOCKER movie has a part where the killer is inside video game?

The movie you're describing is likely "Pulse" (2006). In this Horror film, a malevolent force travels through electronic devices and power lines, leading to a series of terrifying events. The killer manifests in various forms, including a digital presence in a video game. Its themes center around the dangers of technology and how it can connect and manipulate people.