Use GetLocalPlayer to determine the model path used by the effect. For example if GetLocalPlayer is inside the player group then use the visible model path, otherwise use an empty string model path. It is important that both model paths always be declared before such selection takes place to avoid desync. For logical reasons the effect must be created for all clients to avoid a desync, hence why it is created on some with an invisible (empty string) model when they are not meant to see it.