IMO. the same things that characterize strength in men. Just. from women.
Honesty, integrity, kindness. Resilience. a wiliness to speak and do what is right... without necessarily being a jackass about it.
If you were thinking of it in opposition to (toxic) masculinity, the guy who "projects strength" and push their way around.... who call themselves "alpha"... are just assholes. And usually the weakest, most insecure and down right vindictive people you know. that isn't strength. (I can threaten their masculinity just by ignoring them. Pretty fucking pathetic.)
Though there aren't many female heroes in history, the few that existed made huge marks.
St. Olga of Kyiv famously slaughtered (!!!) her enemies (the Drevlians) to protect Kyiv and avenge her husband. She then converted to Catholicism and spread the message to the Slavs. And her lineage then founded Moscow. She's considered the reason why Catholicism spread to the East, despite a patriarchy at her time.
But perhaps bloody stories of revenge and the spreading of the good word (a trope of the Middle Ages I know, but she's known for it), is a bit "Just a man with different bits". Still, she was smart, she was cunning, she was ruthless, she conquered, she ruled.
Perhaps a more traditional "Feminine Strength" is St. Joan of Arc, who raised an army and marched with them, though she never really won battle accolades or ruthless terror like St. Olga. St. Joan of Arc comes from humble beginnings and rises to become a leader of a movement in the 100 years war. Despite being tried for being a witch (erm, talking to the Devil? Something like that), she never gave up on her values and is widely recognized as a key figure in her time.
I think Joan of Arc is closer to what the English-speaking world would consider feminine strength. St. Joan of Arc never betrayed anyone, and largely served as an inspiring figure. (As opposed to the cunning St. Olga who has multiple atrocities in her name). She stood her ground as she was tried, and was burned at the stake at the young age of 19. Still, despite her young age, she was a key leader (though not a ruler), who inspired many to fight for France.
In any case, Joan of Arc was confident. She benefited from prophesies that a maiden would come to save France in the hundred years war, and she stepped up to be that role. She traveled across the country raising and inspiring soldiers. She marched into battle (though I don't believe she was ever seen as a warrior or tactician type given her age and small stature), but this grossly improved the morale of the soldiers around her. Women (or really, young girls) like her weren't supposed to be on the front lines like she was. But just arriving to dangerous positions and being confident, and telling everyone that they're cause is righteous and they're doing the right thing is hugely important.
Being around to witness the horrors of war, to tell people that things are alright and they're fighting for the right things. Its... important. People need to know that.
Note that Joan was also on trial for wearing men's clothes. Suggesting that she's an early feminist who did fight for equality centuries earlier than other feminists. Truly ahead of her time.
There was also Zheng Yi Sao, a chinese woman who became a pirate who was so unstoppable that she even managed to negotiate her retirement with the Chinese government.
My girlfriend can lift heavy objects, so maybe that?
For real though, strength isn’t gendered. There’s strength of character, there’s fortitude, there’s physical strength. But the thing is your final sentence belies a failure to understand just how much these gendered ideas are bullshit. Like whatever the answer is is just whatever the individual values in women that’s difficult. And more scathingly, what is traditionally called feminine strength is the capacity to endure what men do to women.
Assume that a woman isn't just a man with different bits.
Emotional intelligence, empathy, and maturity; knowing when it is more beneficial to be gentle or to just observe/remain quiet; understanding how to take advantage of others' gender-based assumptions/underestimation; and a deep solidarity with other women.
Femininity is something people do, not something inherent to being a woman. (Also, with regard to the way you posed your question, technically a man is a woman with different bits, not the other way around.)
I don't know how to split out socialization from biology, honestly. Are you asking what strengths are considered feminine and are also admired by men? Probably being able to handle physical pain, being good at organizing, endurance in the face of adversity or grief. Ability to read a room, pick up on cues, make people feel comfortable.
Are you asking what strengths are admired by women, what do we consider a strength of women? You will probably get different answers from different women but I think women are often better able to consider a whole situation rather than focusing on one part of it and messing up another part; and that we are usually better at handling physical pain without whining.
If you are asking how willpower feels for me as a woman, though? In terms of deferred gratification?
Probably about how it feels for you. Sometimes easy, sometimes it sucks.
Mom told me that women who reach menopause are suddenly much more likely to initiate divorce, leaving toxic/abusive relationships..
Psychologist Susan Pinker, in her book "The Sexual Paradox", that such women leave careers they'd been pressured-into, by the men in their lives ( ditching academic careers, because the endless-churn-for-"authority-status" isn't what they value )..
I've read the words of a woman who was disappointed to have not got into any of the mixed universities ( UK ), she got into a female-only university, and by the end of week-1, she was euphoric: the absence of sexual-pressure on her all the time, she could learn here!!..
I've read the words of a woman who went to a girls-only grade-school, & she learned, in high-school, that the girls who came from mixed grade-schools had been conditioned into learned-helplessness, and would not even try participating in class, by the boys they'd shared classes with.
I read an amazing item in a Reader's Digest, possibly in a waiting-room, somewhere, on a school-principal who got all the kids and their parents into a gymnasium..
The kids were girls-on-1-side, boys-on-the-other-side, parents in the bleachers/stands..
He asked the kids "who here would rather learn in a boisterous classroom?" The boys, & the dykes, hands shot up..
"Who here would rather learn in a quiet library?" the girls, & a few of the boys ( femboys, prolly ), hands went up.
THEN the parents, who saw, understood, accepting the evidence, instead of the "we're all the same" ideology, that violated that evidence.
Women are more "yin" than men.
The more "yin" a someone is, the more gentle their forming-context/education has to be, in order that their intrinsic nature be allowed to blossom ( as an extreme-contrast, if you've ever encountered an ultra-bullying super-testosterone guy, you maybe can understand that he'd probably be more "educated", if the education were *at his level of pushing, like boot-camp, or something ).
the "yin" or non-pushiness of the someone needs to be matched by the learning-means, the "yang" or pushiness of the someone needs to be matched by their learning-means.
I wish women weren't abused by the entire-education-system, but were, instead, boosted into becoming their own LivingPotential.
That isn't an answer to your question, but it does reframe something important..
Women's courage is like the courage of Florence Nightinggale, who kept digging, until she understood, scientifically, why "her boys" were dying in the forward hospitals, & she pushed graphical representation of her statistics, in order to convince Queen Victoria.
Yin courage.
Yin courage is more .. "watery", more "keep gently working, we'll find a way", as opposed to the more-linear/firey male style of courage.
Like a river, trying to find a way through a blockage put against it..
Gently-persistent, enduring, winning through working with Nature, instead of just arbitrarily overriding it.
The woman who did the classification-system for stars, at some observitory, was demonstrating a kind of courage, given that women had no "validity" in the hearts or minds of men, of the profession, of those days..
The "Famous Five", who broke the "women legally are not 'persons' in the Commonwealth, by law" bullshit also.
( Nellie McLung, iirc, was one of 'em, & a wonderful sentiment of hers goes something like..
"don't let them decide what's allowed, or valid,
but instead, just make things right, & let them howl,"
Now there's a woman. : )
So, as anyone who has seen all the body-language books which identify how utterly-incompetent normal guys are at reading it, women are more-likely to work with & through people.
I think that the masculine strengths are focused on by modern culture and the feminine ignored. The gross becomes everything and the subtle disappears from view.
Maybe marketing culture is to blame. It cultivates a few easy triggers and suppresses everything else.
Oh yeah. Yin and Yang. Feminine and masculine types of energy. Gentle and brusque.
Described as a type of philosophical way of life, the theory suggests neither can do without the other. Full Yin extinguishes, full Yang destroys. Together, they temper the opposite, as equals.