Both. She’s over as a threat this arc, but can still carry on as the friendly Olin in the future.
But one thing I need to mention is that any confrontation between Big Mom and Luffy after Onigashima holds no tension nor would be something cool to see, we have been seeing her fighting style for 200+ chapters, her character, her crew is just oversaturated at this point and I am pretty sure Oda realizes it.