Born in San-Pédro, Kouassi began his career at local side Séwé Sports before moving to Servette FC in the Swiss Super League in 2009.
[6] In September, he received straight red cards in heavy away losses to Atlanta United FC (7–0) and Orlando City SC (6–1), in the 16th and 11th minutes of the respective games.
[9] In February 2020, before the Super League was postponed due to the COVID-19 pandemic, he was sent off in consecutive matches against FC Zürich and Neuchâtel Xamax FCS.
The latter dismissal earned him a public criticism by club owner Christian Constantin, who considered it to have "murdered" the entire team's efforts.
He replaced Gervinho in the last minute of a 4–3 friendly win over Israel at the Stade de Genève, the home of his then-club Servette.