[3] She bounced back from defeat with a ten-round majority decision victory over Julieta Cardozo (11–2) to capture the South American bantamweight title on 2 March 2018 at Club Deportivo Luján in San Salvador de Jujuy, Argentina.
[5] Guanini defended her title against fellow Argentine boxer Micaela Luján on 15 June 2019 with the fight ending in a majority draw with one judge scoring in favour of the challenger 96-94 and the other two unable to split the fighters with 95-95 scorecards.
[6] Guanini was due to fight Rachel Ball for the vacant WBA female bantamweight World title in London, England, on 14 November 2020 but twice failed to make the required check weight despite going to the extreme measure of cutting her hair off.
Subsequently the WBC added its interim female super-bantamweight World title to the contest but Guanini did not make that weight either although she was close enough to allow the bout to proceed with only Ball able to win the belt which she did by unanimous decision.
[10] Guanini lost via unanimous decision to Raven Chapman in a contest for the vacant WBC female featherweight International title on the undercard of the Joe Joyce vs Joseph Parker clash at Manchester Arena in England on 24 September 2022.