The WandaVision star, 48, strutted the red carpet in a sexy strapless black jumpsuit featuring an oversize belt and cropped pants. She paired the ensemble with black pointed-toe pumps and a sparkling necklace with green and white jewels.
But it's what Hahn wears as Agnes (aka Agatha Harkess) on WandaVision that she says was a dream.
"I'm feeling a little jealous of the fact that I didn't have the cash when I was in the 80s to buy some of the clothes," the actress told PEOPLE on the carpet. "So, I felt like I was able to live it out through Agnes."
"I wanted that piano key tie, I wanted that mesh, the fluorescent pink s—, all of it," she added."
Hahn is nominated for Outstanding Supporting Actress in a Limited Series or a Movie for her role as Agatha on the popular Disney+ program. She later told E! that working on the show was "a special thing to be a part of."
"I have such fondness for the making of it," she said during E!'s red carpet coverage. "And the fact that it happened to come at a time where everyone happened to be at home every Friday night to watch to together as a family, that it was multigenerational. It was rare, it's rare to have a show on Friday night that the whole family wants to sit around and watch."
In January, WandaVision star Elizabeth Olsen told PEOPLE that fans should not expect the show to air a second season.
"No, that's easy for me to answer. It is a limited series. It's a fully beginning, middle, end, and that's it kind of thing," the 32-year-old said prior to the show's premiere.
The 73rd Emmy Awards, hosted by Cedric the Entertainer, are airing live from 8-11 p.m. ET on CBS.