In 2017, he signed for UAE Pro-League club Al-Nasr, before moving on a six-month loan to Japanese side Sagan Tosu the following season.

After returning to Al-Nasr for one year, Oumari moved back to Japan in 2019, playing for Vissel Kobe, FC Tokyo and Sagan Tosu.

[5] In June 2008, Oumari – alongside his older brother Hassan who also played regularly for Reinickendorfer Füchse – moved to Regionalliga (fourth division) side SV Babelsberg 03.

[10] His best performance was on 5 March 2010, in 3–0 home win over ZFC Meuselwitz, where he gave two assists and was declared the man of the match.

[6] During the winter transfer window of the 2015–16 season, Oumari moved to Turkish Süper Lig side Sivasspor.

[19] In August 2018 Oumari signed for J1 League side Sagan Tosu on a six-month loan, becoming the first Lebanese player to play in the Japanese top flight.

[26] He scored his only goal for Vissel on 19 October 2019, in a 3–1 home defeat against his eventual future club FC Tokyo.

[33] On 4 January 2021, Oumari played in the 2020 J.League Cup final, helping FC Tokyo win 2–1 against Kashiwa Reysol.

[37] After Oumari's contract expired with FC Tokyo, Sagan Tosu signed him on a free transfer on 25 February 2022.

[39] Oumari made his debut for Lebanon on 7 September 2013, under coach Giuseppe Giannini, in a friendly against Syria.

[41] Oumari's first goal for Lebanon came on 12 November 2015, scoring a 30-meter volley against Laos in the 2018 FIFA World Cup qualification.

[45] On 5 September 2019, the Lebanese Football Association (LFA) announced Oumari's indefinite exclusion from the national team, alongside teammate Bassel Jradi, for refusing a call-up for a 2022 FIFA World Cup qualifying match against North Korea.

[46][47] After issuing an apology explaining his reasons for refusing the call-up, the LFA lifted the exclusions and Oumari was reintegrated to the national team on 19 September 2019.

[48] On 5 June 2021, Oumari scored two goals against Sri Lanka, including a scissor kick, to help Lebanon win 3–2 in the 2022 World Cup qualification.

[8] Reinickendorfer Füchse SV Babelsberg 03 Al-Nasr Vissel Kobe FC Tokyo Individual