Larkin is from
Ringsend and played youth football for the local team Cambridge FC. She also played at youth level for
Home Farm, before joining
Shelbourne. In May 2021, Shelbourne manager
Noel King dual-signed Larkin to the club's senior panel from their
Women's Under 17 National League squad. She scored on her senior club debut, after entering play as an 84th-minute
substitute for
Saoirse Noonan in Shelbourne's 5–0
Women's National League win over
Athlone Town at
Tolka Park on 5 June 2021. In October 2021, Larkin made her first start for Shelbourne when
Noelle Murray fell ill and was unable to play in a league match against
Galway. Larkin was named
player of the match, after scoring a goal and
assisting another in Shelbourne's 2–0 win, which was televised live by
TG4. Shelbourne overhauled
Peamount United on a dramatic final day to win the
2021 Women's National League title. Larkin also played in the
2021 FAI Women's Cup Final, but Shelbourne were beaten 3–1 by
Wexford Youths. Shelbourne announced that Larkin had signed for another season at the end of a successful
2022 Women's National League campaign, in which she helped the club secure a League and Cup
double. However they were disappointed when Larkin subsequently experienced "a change of heart" and instead moved to newly-reformed
Shamrock Rovers alongside some other Shelbourne players. A controversial and swiftly-deleted
tweet on the Shelbourne club account, referencing
The Red Flag lyrics 'Though cowards flinch and traitors sneer', was perceived as being aimed at the departing players and attracted "huge criticism", particularly given Larkin's youth. In September 2023, Larkin joined
Glasgow City. She scored nine goals in sixteen matches across all competitions, before moving to
Crystal Palace in January 2024. ==International career==