Sow made his professional debut for Borussia Mönchengladbach in 2016. In June 2017, Sow returned to Switzerland, agreeing to a four-year contract with Young Boys. He was part of the Young Boys squad that won the 2017–18 Swiss Super League. On 27 June 2019, Sow signed to Bundesliga club Eintracht Frankfurt a contract until 2024.