In 2013, Hermoso left Rayo to join Tyresö FF of the Swedish Damallsvenskan for the 2013 season. In January 2014 she left Tyresö FF to join FC Barcelona. During her three years spent at FC Barcelona, she won two Primera División titles and won the Copa de la Reina twice.
On 3 July 2017 Hermoso signed a three year contract with Paris Saint-Germain. PSG finished second in Division 1 that season, securing a spot in UEFA Women's Champions League, they also won the 2017–2018 Coupe de France.
On 2 July 2019 Hermoso signed a three year contract with FC Barcelona.
In September 2011 she earned her first official call-up for the Spanish national team. In June 2013, national team coach Ignacio Quereda confirmed Jenni as a member of his 23-player squad for the UEFA Women's Euro 2013 finals in Sweden. At the final tournament she scored in Spain's opening game, a 3–2 win over England and also in their 3–1 quarter-final defeat by Norway.
She was part of Spain's squad at the 2015 FIFA Women's World Cup in Canada.
She was also part of Spain's squad at the 2019 FIFA Women's World Cup in France. She scored twice in the opening game of their campaign against South Africa, with both goals coming from the penalty spot. Her first penalty sent South African goalkeeper, Andile Dlamini, the wrong way, slotting the ball to the left, with the keeper diving to the right. In her next penalty, she changed sides, hitting to the right of the goal, the keeper, even though she went the right way, could not keep it out. She scored in the Round of 16 loss to the United States.
|1||16 January 2013||Pinatar Arena, Murcia, Spain||Russia||2–1||2–1||Friendly|
|2||12 July 2013||Linköping Arena, Linköping, Sweden||England||2–2||3–2||UEFA Women's Euro 2013|
|3||22 July 2013||Guldfågeln Arena, Kalmar, Sweden||Norway||1–3||1–3|
|4||27 October 2013||Ciudad Deportiva, Collado Villalba, Spain||Estonia||3–0||6–0||2015 World Cup qualification|
|5||13 February 2014||Estadio Las Gaunas, Logroño, Spain||North Macedonia||3–0||12–0|
|7||10 April 2014||FFM Training Centre, Skopje, Macedonia||North Macedonia||5–0||10–0|
|10||8 May 2014||A. Le Coq Arena, Tallinn, Estonia||Estonia||5–0||5–0|
|11||8 April 2015||Mareo Stadium, Asturias, Spain||Republic of Ireland||1–0||1–0||Friendly|
|12||26 November 2015||Tallaght Stadium, Dublin, Ireland||Republic of Ireland||2–0||3–0||UEFA Women's Euro 2017 qualifying|
|13||24 January 2016||Stadion pod Malim brdom, Petrovac, Montenegro||Montenegro||5–0||7–0|
|14||12 April 2016||La Ciudad del Fútbol, Las Rozas de Madrid, Spain||Republic of Ireland||3–0||3–0|
|15||20 September 2016||Estadio Butarque, Leganés, Spain||Finland||5–0||5–0|
|16||3 March 2017||Estádio Algarve, Algarve, Portugal||Norway||2–0||3–0||2017 Algarve Cup|
|17||8 April 2017||Pinatar Arena, Murcia, Spain||Belgium||3–1||4–1||Friendly|
|19||23 October 2017||Ramat Gan Stadium, Ramat Gan||Israel||0–2||0–6||2019 FIFA Women's World Cup qualification|
|21||24 November 2017||Voždovac Stadium, Belgrade||Serbia||0–1||1–2|
|22||10 April 2018||Bundesstadion Südstadt, Maria Enzersdorf||Austria||0–1||1–1|
|23||31 August 2018||El Sardinero, Santander||Finland||2–1||5–1|
|24||4 September 2018||Las Gaunas, Logroño||Serbia||1–0||3–0|
|26||27 February 2019||Bela Vista Municipal Stadium, Parchal||Netherlands||1–0||2–0||Algarve Cup 2019|
|28||2 June 2019||Stade Gerard Houllier, Le Touquet, France||Japan||Friendly|
|29||8 June 2019||Stade Océane, Le Havre, France||South Africa||2019 FIFA Women's World Cup Group B|
- Rayo Vallecano
- FC Barcelona
- Paris Saint-Germain
- Coupe de France Féminine: Winner 2017–18