The dummy is the dimplest of the no crying sleep solutions. You're late to be introducing one at 9 months old and having it accepted, but I assume you've tried?
In terms of gentle sleep training ' you first need to set yourself some realistic expectations. Yes, it's possible. But it will not be quick. In fact t it will take a long, long time. We are talking many months, possibly a year or more if you want to do this very grafuskky to not create and distress.
So not a quick fix. But if you can gain some perspective and acceptance, you'll feel less stressed about the wake ups and just accept they will happen but af least things are ever improving.
Then have a look at The Pantly Pull off. It's a gentle sleep training method to stop breastfeeding to sleep. You pull baby off the breast progressively earlier until you are cuddling to sleep rather than breastfeeding to sleep.
Then you spend many months nakibg tiny gradual changes so cudfling to sleep becomes cuddling in the cot to get to sleep. Then just reassurance in the cot. Then just reassurance from in the same room. Then self-comforting us in the child's own comforting mechanism.
So I did this with my youngest. No crying. I would not ever tolerate any amount if distress and always gave her all the comfort she ever needed. We stared this ethos from birth. So the difference in my case is that there were no sleep associations, it was a clean slate (dd is my 4th child, I learnt from very many mistajes). She was settling in her cot by 6 months, occasionally sleeping thro by 9 months and by 12 months could be placed in the cot standing and would get herself to sleep (with a dummy and blankie).
So from birth it took 12 months. You are starting from much older and with sleep associations already in place. Therefore its reasonable to expect if you want to do this the no-distress way, it may take 18-24 months.
If you could speed the whole thing up. This will involve some dustress but you will be tgere there to comfort her. It depends on if you truely want to do this gently and slowly enough to cause no crying or upset.