My eldest went through this phase at a little older, it started after he got bitten in nursery, but extended to leaving the house to go anywhere. He was non-verbal at that age, and has since been diagnosed with autism, however the strategies we used are useful for any child with emotional disregulation. After a lot of trial and error, this is what worked for us:
-A visual timetable that DS would put the pictures on each morning, so he had control over what order he did things in
-Minimal language used during the meltdowns, trying to reason/talk him down at that point made things worse, he needed time to get his feelings out of his system, then I could talk
-Leaving a ridiculously long time in which to get ready, and sense that I was trying to hurry him along and he would get overwhelmed
-As he got slightly older, making it clear if we were going to be leaving he house the following day, where we were going, how long we were going to be there, and how much time he would have at home at either side of the trip
2 is a tough age, the other parents you've spoken with might not be able to relate to your DD's specific behaviours, however it's really not uncommon. How is she once she's out of the house? Does it take her time to calm down, or once the 'getting ready' is over do her feelings subside. If she's feeling overwhelmed when she leaves the house as well, perhaps trying things like short trips out, using ear defenders, taking food and drinks with you so you always have something familiar to hand, taking a blanket if she might find cocooning herself comforting.
DS is 9 now, and still finds uncontrollable environments challenging, we go places armed with the things he needs to help him regulate, however we have progressed from leaving he house 'kitted up' so to speak, to just having these items in a bag and he will ask for them if he needs them, so his resilience is building.
DD is 6 and is on the assessment pathway for autism and pathological demand avoidance, so she can be really explosive at times. We manage better at home because she has more control, but she is finding school deeply challenging at the moment. She is academically behind, and has recently become aware of that fact, which is causing lots of meltdowns as she's feeling the pressure to catch up with her peers so she can do the same tasks they are. For her I've been reading up on low demand parenting which was recommended on another thread. A lot of it is what we are already doing, but there have been some useful insights, it might be worth a look for you too based on some of the things you have said in your posts.
It's tough, but you're doing your best. Sometimes we find strategies that work, other times they outgrow the behaviours as they mature, but either way, it won't be like this forever. If she gets older, and is still displaying a lot of these behaviours, it might be worth considering assessment for some form of neurodiversity, but for the moment, she's barely more than a baby, with a lot of feelings she doesn't know how to handle. It sounds like she has understanding and supportive parents from everything you're trying, she will learn in time.