She described as the upcoming second instalment as "a real girl power, badass kind of superhero type of movie".
"They're really strong, the two sisters, and it's exciting. The music is beautiful," she added.
Broadway star Menzel compared her voice role to that of Elphaba in Wicked, for which she won a Tony Award in 2004.
"Elsa, Elphaba, they're young women that are afraid of their incredible power and then learn a way to harness that," Menzel said. "The power and beauty of fierce, incredible women… not apologising for who you are, especially in this time we're in."
Frozen 2 will be released in November 2019 and although the plot is not yet confirmed it's set to see Evan Rachel Wood and Sterling K. Brown join the cast in new roles.
Alongside Menzel, Kristen Bell reprises her role as Elsa's sister Anna, Josh Gad returns as Olaf and Jonathan Groff is back as the voice of ice harvester Kristoff.
A first trailer for the sequel was released in February and notched up almost 120 million viewers in 24 hours, making it the biggest animated film trailer of all time.
The two minute clip features Elsa attempting to use her ice powers to cross a raging sea, before joining Anna, Olaf and Kirstoff overlooking a mystery new land.
You can watch the teaser trailer for Frozen 2 below...