Holmberg made one senior appearance for
Älvsjö AIK in 2022 before joining Hammarby IF’s first team later the same year. In late 2022, she trained with
Olympique Lyonnais during a visit to France while still under contract with Hammarby. Holmberg debuted in a
Svenska Cupen match in late 2022 and became a regular part of the squad during the 2023 season, contributing to the club’s Damallsvenskan and Svenska Cupen titles. In May 2024, she extended her contract with Hammarby until the end of 2026. During the 2025 season, Holmberg emerged as one of the team's top scorers, registering four goals and one assist in the opening four league matches. On 5 January 2026, it was announced Holmberg had signed for English side
Arsenal. On 10 January, Holmberg made her Arsenal debut, coming on as a substitute in the 83rd minute, in a 0–0 draw against
Manchester United. Later that year, on 29 April, she scored her first goals by netting a brace in a 7–0 win over
Leicester City. ==International career==