On January 13, 2021, Otto was selected first pick of the second round (11th overall) of the NWSL Draft by Racing Louisville.[3] She made her debut for the side on April 15, 2021, in the NWSL Challenge Cup against the Washington Spirit, coming on as a 78th-minute substitute in a 1–0 defeat.[4]
On July 27, 2022, Racing Louisville announced that Otto had mutually terminated her contract with the club to pursue playing opportunities in Europe.[5]
Celtic
On August 7, 2022, Otto signed for Celtic, and she made her Celtic debut in a 9–0 win against Hibernian.[6]
Gotham FC
In July 2023, Otto joined Gotham FC as a national team replacement player, due to six players of the club being selected to play in the 2023 FIFA Women's World Cup.[7]
Melbourne City
In September 2023, Otto joined Australian club Melbourne City on a one-year deal.[8]
Otto impressed after starting every game of the 2023/24 campaign and re-signed for another year on June 14, 2024. She will be an important member of Head Coach Dario Vidosic's inaugural AFC Women's Champions League squad.[9]