[1][2] Kostons progressed through MVV's youth academy, joining their setup as a thirteen-year-old from boyhood club Lanaken VV.
[3] He made his debut on 19 September 2017 in a 3–2 loss to AZ in the KNVB Cup, replacing Christophe Janssens in the 90th minute.
[5][6] Kostons made his league debut on 6 October 2017 in a 3–2 loss against Almere City, coming off the bench in the 88th minute for Shermaine Martina.
[11] He was part of Dalkurd's promotion to the second highest level in Sweden, Superettan, scoring 11 goals in 16 appearances.
[13][14] He made his return debut for MVV on the first matchday of the 2022–23 season, starting at forward alongside Orhan Džepar in a 3–1 loss to Jong AZ.