Addison debuted for C&K Basildon's senior team in their 2016–17 FA Women's Premier League season, making 16 appearances and scoring 11 goals.

[2] After the season concluded Addison joined former WPL opponents Tottenham Hotspur, moving up to the FA Women's Championship and playing semi-professional football for the first time.

[4][3] She made her first appearance for the club on 19 September 2018 in a match away to Leicester City as a substitute for fellow midfielder Sarah Wiltshire.

[9] In July 2019 it was announced that Addison was among the players Tottenham retained from their Championship squad for their debut WSL season.

[16] In October 2021 Addison received her first call up to the England women's national under-23 football team, but she along with her Spurs teammates were recalled from the camp.