Honestly you might be better readjusting your expectations. It also depends on your time frame expectations. I would say with a decent amount of confidence you can get her settling and sleeping in her cot within a few years.
Worth noting that the "regression" people talk about is not a regression in the sense that you struggle through it, it gets better then things go back to how they were.
It's actually a perminant change. The physiology of how baby sleeps changes as baby comes out if of the "fourth trimester". Sleep is no longer the passive state of the newborn or foetus in-utero. Sleep is now active and has to be actively worked-at to get baby to sleep and to stay asleep between one sleep cycle and the next.
The regression will last as long as it takes for you and baby to work out the best way for baby to get to sleep and stay asleep. You've used cosleeping for that, which is perfectly fine. But your expectations are out.
The next change in sleep happens around school age, 4-ish years old (anywhere between 3-5 years). At this point the child can sleep like an adult - tired, lie down, close eyes, sleep. Until then the babies brain development will require some form of comfort soothing to get to sleep.
There are parent led soothing techniques (cosleeping, breastfeeding to sleep, rocking, cuddling).
There are independant soothing techniques (dummy, comforter blanket or toy, thumb sucking, self-comforting rhythmic movement a like hair twiddling, parting, rocking, head shaking)
You have at the moment found parent-led settling works best for you. This is likely to last as long as it takes for you to develop an independant soothing method as a replacement. Or until school age. Whichever comes first.
Personally, I'd be finding gentle ways to settle baby to sleep independantly in the cosleeper cot, without being fed to sleep. But I know loads of families who decide to go sleep and feed to sleep and are completely happy with this. But they don't have expectations that things would change within the first year or two. They made peace with that, stopped stressing and just enjoyed the cuddles.