Her performances for Spain's youth and senior teams and Barcelona have made her widely considered one of the best midfielders in the world.

[10] In the semi-final of the 2017–18 Women's Champions League, she scored her first ever UWCL goal away at Lyon that helped keep Barcelona in the tie.

[11] In the home leg, however, Barcelona were victim of a Eugénie Le Sommer strike that Guijarro nearly knocked off the goal-line, and exited in the quarter-finals to the eventual tournament winners.

[13] She started the final against Atlético Madrid that went to extra time and was rescued by a Mariona Caldentey goal in the 122nd minute that won her her second Copa de la Reina title.

[14] For a large portion of the 2018–19 season, Guijarro was sidelined with a ganglion cyst injury on her right foot that lasted almost 5 months and required two operations.

[3] She was discharged from injury hours before the 2019 Champion's League final, but did not feature in Barcelona's 4–1 loss to Lyon later that day.

[16] In February 2020, she played in the first edition of the Supercopa de España Femenina, and was the first Barcelona player to score in the semi-finals against Atlético Madrid with an outside the box volley.

[17][18] She started the final against Real Sociedad, a 10–1 win that earned Barcelona and Guijarro their first ever Supercopa de España Femenina trophy.

[19] In the first game of Barcelona's 2020–21 league season, she scored the first goal in a match against Real Madrid Femenino, making her the first goalscorer in the Women's Clásico.

Guijarro's first international youth tournament experience came when she was fifteen, with a callup to play for Spain at the 2013 UEFA Under-17 European Championship.

[29] A 4–0 thrashing of Germany put them at the top of their group and found them playing England in the semi-finals, a match they won 2–0.

She scored Spain's first and only penalty as Germany exacted revenge for their group stage loss by defeating them 3–1 in the shootout.

She scored the game winner and her second tournament goal in that match, allowing Spain to finish second in the table with 6 points as they moved onto the knockouts.

Guijarro scored the game winning third goal in the 77th minute, securing Spain's trip to their fourth consecutive U19 EURO final even after they would concede again in the 85th.

As the match advanced, the scoreline went to 2–2 until the 89th minute when she scored her third match-winner of the tournament with a headed goal off of a Carmen Menayo free-kick.

[53] Before the final, England forward Georgia Stanway tied her six-goal tally in the third-place match against France.

They both ended their tournaments with six goals and she shared top scorer honours with Stanway, but Guijarro earned the Golden Boot by registering an additional three assists.

[56] Her first senior international goal was a 91st minute match-winner that came in a qualifying match against Serbia, keeping them on top of the qualification group.

At the 2018 Cyprus Cup, she played in two of Spain's group stage matches- two wins against Austria and the Czech Republic.

[60][61] Seven points and a +3 goal difference at the end of the group stage meant Spain were to face Italy in the final of the tournament.

She made her World Cup debut in the next match, a group stage clash against European powerhouse Germany, subbing on in the 65th minute for Silvia Meseguer.

[64][65] She was one of Las 15, a group of players who made themselves unavailable for international selection in September 2022 due to their dissatisfaction with head coach Jorge Vilda, and among the dozen who were not involved 11 months later as Spain won the World Cup.

[69] In 2018, club and country teammate Aitana Bonmatí also felt that Guijarro helped the team "by making runs into the box".

Using her speed and physicality to break past markers, Guijarro is able to finish moves she starts and contribute in attack.