Is it absolutely necessary to create a control blueprint for Multiplayer games?

So when I started designing my game I had initially put all my move functionality in the character blueprint event graph. If I understand right this will not allow a multiplayer game to function properly and a control blueprint needs to be created for the Camera and Character Movement. Is this 100% true? I’m asking because setting up a controller to a character blueprint is kind of a pain in the *** and feels like double work.