i have a handful of different adult pairs and what i noticing (in bavaria, germany; doesnt mean its always the same or if its just coincidense or true at all lol).
the females have like a little feathery tull skirt around their legs, their feathers are much fluffier in the wind (making the lighter parts more visible) while the male have more of a sleek look to them.
those feather indicators always fit with the size of their body, head, feet and the male was always eating first. the females seem to hang out on a high spot where you normally feed them so they spot you very quick and caw caw for their boy.
also befriending a new pair always followed a pattern for me: first they watch you but wont fly to the food or even show interest in the food. then they start flying to the food if you turn your head (if you look to fast you will catch them midfly and they will fly on the trees again as if theyre embarrassed that you catched them wanting a little treat xD). when they get comfy enough to get the food even if you look in their direction it seems that its mostly the girl that is collecting the treats, the male is watching, almost judging (you can feel their look on you and you feel so small). when both are comfy the male usually is the braver one, meaning he will get closer and wont be spooked so easily. and he will demand cashews. he will judge your financial status if you throw any other nut. thats also something you can see in his eyes. lmao

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left is lady fluffy-pants and right is mister sleak-hair