Your pic is tight I can't see your hive setup.
I am over-wintering in a 2 box brood setup (a deep and a medium), with an R10 insulated lid and solid bottom boards. I am feeding to keep the mediums full going into winter.
I have not had to use a robber screen this year.
https://i.ibb.co/P6x5HvJ/20220929-084312.jpg
The reduced entrance sizes I am using this year have eliminated robbing it seems. They have no problems dragging out the drones or clearing any carcasses. I have found it best if the bees don't have to lift anything they remove from the hive. I have all my entrances even with the hive floor and level or sloping away from the hive.
How much honey have they put away? Hive weight? (tip the back side to feel the weight) They will need between 50 and 150 pounds of honey to overwinter depending on genetics, weather, hive condition/setup and colony size.
You can feed syrup until the weather turns, when the syrup gets cold they won't take it. After that you can feed fondant or dry sugar if needed.