She's had a few changes over the years. I think what sticks out to me is the first year or two she really played into her kusogaki character. At some point she started normalizing into who she is today which is a calmer and more mature character. To be honest, I think her earlier streaming years were more true to how she really is and represent a lot of why I originally got into her. That core aspect of her character isn't gone and often still surfaces the more fun she's having. It's pretty much any time she drops down to her normal vocal register. It also reflects in the way she laughs.
These days when she's calm or just started streaming (on schedule) she often does a kind of laugh she just uses to carry on the banter https://files.catbox.moe/4k8gmk.webm I remember her starting do this around the time she moved (for the second time?), but it may have happened earlier. It was around the time the acoustics were bad and it sounded like she was streaming from a bathroom.
She also adopted a more gremlin-ish laugh that I think she picked up from Asumi. I can't find a good example at the moment and she doesn't really do it anymore. She did it a lot around the time she was playing RUST.
When she's really having fun you'll know it. A good example is her most recent collab with Hoshikawa, when she was playing kanji de go, or when she had that great Outlast collab with ikkisei and laughed when they were being hunted by the naked grunts. My favorite is when she spotted 四万十市奥屋内へき地 playing GeoGuessr https://files.catbox.moe/4biqeh.mp4
Very rarely these days will you see her fully be comfortable doing her own thing and just going full 大爆笑 https://files.catbox.moe/vnj0p6.mp4
I think she also had more of a nervous energy when she was just starting out and was less technical. There's a pretty old clip of her not knowing why her minecraft looked so bad with the reason being she had plugged her monitor into integrated graphics or something. You could tell she was stumbling along back then. Just look at how she is in this (really good) clip https://youtu.be/VzoDDbaV8Vc?t=34