After her first World Cup win in Italy in 2019, she renounced her United States citizenship for Chinese citizenship in order to represent China at the Beijing 2022 Olympic Winter Games.
American media outlets have covered her competing for China, and some even say she is a naturalized Chinese citizen, I couldn't find anything about renouncing U.S. citizenship. That may be because, according to The New York Times:
Gu declined to comment when asked about her citizenship status. China does not allow dual citizenship, but there is no official record that she has given up her American citizenship.
Archive to bypass paywall:
Eileen Gu renounced her US citizenship to compete for China in the Olympics. As an Asian-American, I have some thoughts https://archive.is/lYLl9
They sourced this from her profile:
Ailing Eileen GU https://olympics.com/beijing-2022/olympic-games/en/results/freestyle-skiing/athlete-profile-n1058695-ailing-eileen-gu.htm
American media outlets have covered her competing for China, and some even say she is a naturalized Chinese citizen, I couldn't find anything about renouncing U.S. citizenship. That may be because, according to The New York Times:
Eileen Gu Is Trying to Soar Over the Geopolitical Divide https://www.nytimes.com/2022/02/03/sports/olympics/eileen-gu-china-freeski.html