[6] Emreli made his European debut in 2016 against Luxembourgish F91 Dudelange in the second qualification round of the UEFA Champions League which ended 2–0 for Qarabağ.

[7] On 15 September 2016, Emreli made his debut for UEFA Europa League group stage game against FC Slovan Liberec.

[9] Emreli made his debut for UEFA Champions League group stage game against Chelsea in Stamford Bridge on 12 September 2017.

On 18 August 2020, Emreli, scoring against FK Sileks at the first qualifying round of the UEFA Champions League, celebrated his goal with a salute to the Azerbaijani soldiers serving in the frontline during the border clashes with Armenia.

[14] On 26 August 2021, during play-off match of the 2021–22 UEFA Europa League against Slavia Prague, following an unsuccessful 0–1 first half, Emreli scored two goals and secured Legia's qualification to the group stage of the tournament.

[20] On 24 August 2022, Emreli played in the play-off match against FK Bodø/Glimt with Dinamo Zagreb winning 4–1 and ensuring a place in the 2022–23 UEFA Champions League group stage.

[29] In May 2019, Mahir changed his surname from Mədətov to his mother's family name of Emreli, expressing disapproval at his father's marriage to another woman.