I did the Oh Crap method with both and it was great. My oldest self-iniated on Day 2 and was staying dry overnight within the week. She was on the unicorn side of things. We still had minor regressions, etc, but overall she took to it really well. With my second it was a longer process, but he did well too. It was a few weeks before we went from commando to underwear. First attempt around 21 months (Labor Day weekend) was an utter failure so we did a reset and tried again around 27 months (Pres Day weekend). It helped that our daycare was familiar with the method and completely supportive. There's a FB support group that's super helpful as well.
I'd be interested since mine is little as well but in what others are saying but for now we are just offering potty-tunities So first poop of the day is normally in the morning so we try the potty every morning and we catch the first poop most of the time! Just to get him used to the potty and the feeling of needing to go. We use sounds for pee and poop and aren't stressing it now but are happy to have one less diaper change until we more formally start potty training!
You could look into elimination communication. Can start it at any time even part time.
I'll be starting soon with my 12m old. Following to see what others suggest!