A user equipment (UE) device may reside in a state of dual connectivity with a master cell group (MCG) and a secondary cell group (SCG), wherein the radio access technologies of the MCG and the SCG are different. While in the dual connectivity state, the UE device may transition to a mode of reduced activity (e.g., processing and/or RF activity) relative to the secondary cell group (SCG) in order to save power, e.g., when traffic flow via the SCG is below a threshold, or when scheduling activity on the SCG is low. Various mechanisms may be employed to reduce activity, e.g., mechanisms such as reduction of beam monitoring, deactivation of secondary cells of the SCG, reduction of number of active antenna elements, employment of longer periods for periodic measurement and reporting processes, etc.