Ansah, the son of former Southend United player Andy Ansah, had spells with Sydenham Sports club and Charlton Athletic before joining the academy at Arsenal at the age of 10, who beat off interest from several other London-based clubs including Tottenham Hotspur and AFC Wimbledon.
Arsenal
Ansah made his way through the clubs youth system, making his debut for their under-18 side at the age of just 14 and later impressing in the NextGen Series youth competition. On 4 December 2012, with Arsenal already qualified for the next round of the competition, Ansah was named as a substitute for the clubs Champions League group stage match against Olympiacos but remained on the bench during a 2–1 defeat. At the end of the 2013-2014 season, Ansah was released by Arsenal without making a first-team appearance.
Charlton Athletic
Ansah subsequently joined Football League Championship side Charlton Athletic on a two year deal, working with under-21 development manager Jason Euell.
He then scored Plymouth Argyle"s first goal of their League 2 Play-off tie with Wycombe Wanderers at Home Park, his goal making the scoreline 3-1 in Wycombe"s favour at the time. He made a total of 10 appearances for the club, scoring twice.
He returned to Charlton when his loan ended on 12 December 2015. Ansah has represented England at both Under-16 and Under-17 level
In 2012, at the age of 18, Ansah was called up to the Ghana under-20 side for the first time but both Ansah and his father Andy blasted the Ghana Football Association stating that they had not been notified of the call-up and had discovered it after a family friend had messaged to congratulate him.
Ansah later committed his international future to Ghana and, the following year, he was called up to the provisional under-20 training squad to train with a view to being included in the squad for the 2013 Fédération internationale de football association U-20 World Cup but was later omitted from the final squad.
He suffered a tear of his Anterior Cruciate Ligament in July 2013 that ruled him out for eight months, the second time he had suffered the injury, but returned to the development squad in March 2014, scoring in a 5–3 win over West Ham United. In March 2015, he joined Football League Two side Plymouth Argyle until the end of the 2014-2015 season, scoring on his debut for the club, the third goal in a 3-0 win over Cheltenham Town. In August 2015, Ansah returned to League Two, joining Newport County on an initial one month loan deal, making his debut in a 3–2 defeat to Leyton Orient.On 24 October 2015 he scored his first two goals for Newport in the 4-1 win versus Bristol Rovers.
