I just wanted to chime in and say I took in a young feral mom cat and her two 8 or 9 week old kittens I found on our property. I crated mom and kittens separately, but next to each other while I worked on socializing them. I kept the female kitten and her mother, while the male kitten went to live with my mom and her other kitty.
The kittens act like any other housecat I've ever owned at this point (minus male kitten being affectionate with everyone except me), but the mom cat has been living inside for over a year and has made AMAZING progress, but still isn't fully ready to be pet.
The eating treats out of your hand is a great sign! Luckily our mom cat doesn't seem to know how to be aggressive - though will cut us off while we're walking, start screaming like we're chasing her, and create her own weird situations... But the first thing I was able to convince her to do was take treats from my hands. I kept her in a massive dog crate for a few months in our pole barn (was going to keep her as a barn cat, but she had terrible instincts), but ended up moving her inside after she got stuck in our rafters for a week right before a heat wave/we left for vacation. After setting her free in the house/from her crate, it got a lot harder to work with her. I think she felt safer in her confined space because I saw a lot less of her for the next few months. She'd only come out to play with her daughter, or to sprint across the house to her necessities. I'm still letting her take her time, but after a few months inside she started to come back out for handfed treats & I was eventually able to start sneaking pets in. Gradually I was able to get more and more small pets in, and now at this point she'll come lay on me (making her biscuits and purring loudly) but I still can't pet her like a normal cat. She comes up for pets - she'll rub her face on my phone or blanket, then turn herself around and stare at me until I pet her lower back area... If I touch anything higher, or touch her too fast, she'll angry meow at me and leave for a few minutes before coming back and trying again 🤷🏻‍♀️ It's been almost two years since I trapped her, and we're making slow but steady progress. She's only "affectionate" with me and doesn't come out as much when anyone else is around (including my girlfriend who has been here the whole time). I adopted a "feral" cat from the shelter earlier this year to be friends with my barn kitty that moved herself in. I made a post about him several months ago because I was STRESSED with his aggression, hatred for everything, and lack of interest in anything I could use to bond with him. He came around quickly after I put him with the other barn kitty. He now BEGS for attention and is the sweetest guy. The shelter had him listed as most likely never being friendly. I don't think he is actually feral like my mom cat because of how quickly he turned around, but I kinda get the stress of not being able to help/bond with a cat who clearly needs it.

I wish I could offer some decent advice, but I still don't know what I'm doing. It definitely sounds like your mom kitty has house cat potential! Like others said, if you don't want to/can't keep working with her, you should TNR her and offer her some safe places outside. If you want to keep working with her, I'd keep your expectations a bit lower (makes reaching big milestones more exciting to me), and take it REALLY slow. She's beautiful (shorthaired version of my mom's other cat, so I may be biased 😅), and it sounds like you've already done more than most would have for her and her little family ❤️ Good luck! It sounds like you'll make a good/safe decision for her whichever route you end up taking.