In 2019, he began training with the first team, and on 25 August 2019, he made his debut for Legia in a 3–2 away win against ŁKS Łódź, providing an assist for Dominik Nagy.
[11] Karbownik made his debut for Brighton on 10 February 2021, starting and playing the full match in the 1–0 away defeat against Leicester City in the FA Cup fifth round.
[12] He made his second Brighton appearance and first of the 2021–22 season in Albions' 2–0 away victory over Cardiff City in the EFL Cup second round on 24 August 2021.
[13] On 28 August 2021, it was announced that Karbownik would join Greek champions Olympiacos on a season-long loan with an option to buy.
[17] On 8 August 2023, German side Hertha BSC announced the signing of Karbownik on a three-year deal.
[citation needed] On 7 October 2020, one day after completing his transfer to Brighton and Hove Albion, he debuted in a 5–1 victory against Finland, providing an assist for Arkadiusz Milik.