“The choices you’ve made, romances you’ve pursued, your class, etc., are all a part of who your character is, and those decisions will be honored in Knights of the Fallen Empire; often in unexpected ways,” Boyd says. He also mentions companions, saying that “there’s a ton of stuff going on with companions in this release.” While he avoids specifics, Boyd explains that past companions will return, sometimes as “very critical” parts of the overall story shared by all Outlanders.
Source: Forums