Any given control input and power level will eventually stabilize to a particular flight characteristic given time. (In other words, Pitch + Power = Performance.) Even if the aircraft is in a turn when controls are lost, it should just continue to turn.
Now, if engine power is lost, then airspeed would bleed off and a stall might result. It's possible the stall could develop into a spin, and in some aircraft designs it could even be a flat spin.
What's confusing me is why
engine power would be lost. All else aside, jet turbines don't require electricity to keep them going. Maybe to get them started, but that's all.