I had some good interactions even in the treat trails. Some of the stages have an area cleared now where you can try to snap a quick pic or in Ernesto's case listen to him singing.
Going by last year:
Yokai is a definite no for interactions, he just stands there and looks menacing.
Judge Doom does the routine, then walks around or sits looking menacing. Interaction also not possible due to the set up.
Ernesto De La Cruz also mainly did his act and sang, but for him at least they had cleared up an area where you could stand and listen to him singing. That was an insane problem the year before, the stage area was so congested.
Oogie Boogie: If the line is slow enough (so basically through the parades and that is it) he may notice if you try to take a selfie and pose really quick, but that was it.
Sid: He picks people to heckle. You may or may not get a good interaction out of it, his line was always crowded.
Mother Gothel: Her stage is very close to the actual trail, so there is a decent chance at interaction, especially if you have children in the group. I saw her spending several minutes talking to a Rapunzel group last year.
Cruella: that line can get ridiculously long. I got lucky there and managed to hit it when the line was dead. She noticed my camera with the large zoom lens. I took my chance and yelled "Miss DeVil, are you ready for your photoshoot?"She really put on a show for me, walking around doing poses. Even came to the edge of the stage for a selfie.
Agatha: she will come down from that pedestal once in a while. Lot of the interaction then is clearly scripted too, but she will come down to the rope, talk to people and occasionally take photos.
And my personal winner: Madam Mim. I had really good interactions with her in 2022 already. Again no one really stopped when we visited, so we started some banter. She asked me if I wanted to be her BFF in the end and of course I agreed.
Then 1.5 weeks later I came back for another party with other friends, and when I said "Hi Mim!" she actually remembered me by name and told me she had been worried her BFF left for Germany without saying good bye. As my friend put it: "I could tell the exact second she had you turning into a puddle."
So last year I had decided I was going to dress up as Mim. It wasn't even a big dress up, I can't sew for the life of me. So Mim wig and a Mim themed t-shirt it was. I was among the first in line for her treat trail. One of the CMs opening the doors spotted me, chuckled and said: "Oh she is going to love you!!!" And boy was he right. She screeched, came running across the stage and called out for me as soon as I came in her line of sight. I had a Paris pin of her with me because the year before she had been lamenting there never was any merchandise of her. So she gushed about my outfit, I got to give her the pin and she really made a show out of that, and then she asked me if I wanted to take a portrait with her. Oh yes PLEASE!!! I turned my back to her to try for a selfie and she yelled "no no no a proper portrait!!!" and then yelled for a CM to take our picture. It was totally insane and well worth every second of getting plastic hair stuck on my face and in my mouth.
