Villalibre scored his first professional goal for Bilbao Athletic on 6 September 2015, closing the 3–1 home win over RCD Mallorca.[5] At 17 years and 341 days, this made him the second-youngest goalscorer for the team when competing in the second division (behind Ander Garitano's 17 years and 198 days in 1986).[6]
On 3 December 2016, Villalibre was called up to the first team for the Basque derby against SD Eibar, with habitual first-choice Aritz Aduriz suspended after being sent off in the previous league match.[7] He made his La Liga debut the following day, replacing Iñaki Williams after 84 minutes and providing the assist for Iker Muniain to score the final goal of a 3–1 victory in injury time.[8]
Villalibre appeared in his first game in European competition on 8 December 2016, contributing another decisive pass in a 1–1 draw away to SK Rapid Wien in the UEFA Europa League group stage after once again coming on from the bench.[9] He was loaned out to CD Numancia on 2 May of the following year, for one month.[10]
On 20 August 2017, Villalibre was loaned to second-tier club Real Valladolid for one year.[11] After only netting twice in the cup, his loan was terminated and he subsequently moved to Lorca FC of the same league also in a temporary deal.[12]
Villalibre scored his first league goal for Athletic on 25 January 2020, playing 84 minutes in the 1–1 away draw with RCD Espanyol.[13] The following 17 January, his last-minute equaliser against FC Barcelona earned extra time and an eventual 3–2 win in the 2021 Supercopa de España final; he was also the target of an aggression that earned Lionel Messi the first club red card of his career.[14]
After totalling 35 games and four goals in 2020–21, Villalibre fell down the pecking order the following years,[15] and was loaned to Deportivo Alavés on 30 January 2023.[16] He scored twice during the second-division play-offs to help the club to gain promotion, starting with a 2–0 victory over Eibar;[17] in the second leg of the final at Levante UD, his penalty deep into injury time of extra time was the tie's only goal.[18]
Villalibre made his debut for the unofficial Basque Country national team in May 2019, in a 0–0 draw away to Panama for which a small, youthful and inexperienced squad was selected.[29][30]
^Martín, Javi (10 September 2015). "Villalibre: El debut soñado con 15 años" [Villalibre: A dream debut at 15 years] (in Spanish). La Cantera de Lezama. Retrieved 4 September 2016.
^Callero, Borja Luis (4 December 2016). "Un león a la carrera por Europa" [A lion runs loose in Europe]. Marca (in Spanish). Retrieved 4 December 2016.
^Rodríguez Beltrán, Javier (17 January 2024). "Villalibre: "Dentro del campo no hay amigos"" [Villalibre: "No such thing as friends on a pitch"]. Diario AS (in Spanish). Retrieved 11 April 2024.