"I've never really seen anyone treat extras like that, to that level of, 'Ugh, don't look at me, don't make eye contact, ugh cockroaches, there they are,'" Edwards, 34, told The Sun.
"I think I was even on a different show and someone was like, 'Oh, you know Lea's a b**ch, right? She calls the extras 'cockroaches'."
Edwards played a dancer on Glee who was in the hallway during a New York "audition" that Michele's character Rachel Berry was attending.
In the scene, Rachel had to storm out of the room, past the extras.
"Take after take she had to walk by me in a huff, but in between certain things would just happen," Edwards recalled.
"She walked by me and burped in my face, this loud burp, directly almost face-to-face, it wasn't even like, 'Oh she wouldn't have known.' She knew she burped in my face.
"Two other people saw it and an operator said, 'Oh my God, I'm so sorry she did that.' I was just like, 'Yeah, whatever.' You're on set trying to be professional, you're not trying to make a huge deal about things.
"(After) the second or third take she walked by me and stepped on my foot really hard. You know when you bump into someone you can feel it, again nothing, no reaction, like I wasn't there.
"Another extra rolled her eyes like, 'Wow, that's so like her to not acknowledge.' It made me feel like I was nothing, even if she just said in a half-a**ed kind of way like, 'Oh, I'm sorry,' but no."
Edwards also weighed in on allegations that instances of Michele's bullying were racist.
"That's heavy, I don't really like to pull that card, (but) if she is racist then she should be called out," Edwards told the publication.
"She did treat me like I was nothing, like I wasn't even worth making eye contact with, so maybe. These things can offend and hurt us, and sometimes they don't know what they're saying or maybe they think they can get away with it – 'Oh it's just a black person, they don't really care, they're less than.'"
On Tuesday evening, Michele shared a lengthy statement, in which she wrote that while she didn't "remember" the specific behaviour she'd been accused of, she had "clearly acted in ways which hurt other people".
"Whether it was my privileged position and perspective that caused me to be perceived as insensitive or inappropriate at times, or whether it was just my immaturity and me being unnecessarily difficult, I apologise for my behaviour," Michele said.
Her apology came after Samantha Ware – who played Jane Hayward on the hit musical series for its sixth season in 2015 – responded to a tweet written by Michele amid the riots in the US, claiming the actor made her time on the show a "living hell".
In an all-caps response to Michele's post, Ware wrote that she would "never forget" the "traumatic microagressions" she claims to have received from the star – including a shocking allegation that she had "told everyone that if you had the opportunity you would 'sh*t in my wig'."
Far from putting a stop to the flow of bad press, Michele's apology sparked a wave of backlash and a fresh round of accusations.
Among them were two of her former castmates from Broadway musical Spring Awakening, in which she starred from 2006-2008, who described her as a "nightmare" to others on set.
"You were nothing but a nightmare to me and fellow understudy cast members. You made us feel like we didn't belong there. I tried for years to be nice to you to no avail. Maybe actually apologise instead of placing the blame on how others 'perceive' you. You'll probably just delete this comment though," Gerard Canonico wrote.
Another Spring Awakening star, Emma Hunton, was also quick to criticise Michele's statement, writing simply: "This isn't an apology."
