Richardson sat out a year after college[3] and first joined TuS Elbingerode (later named Bodfeld Baskets) of the German Landesliga (seventh-tier) in 2009.[4] Across the 2009-10 season, he averaged 48.8 points a contest,[5] helping the team climb to the next higher league. In the 2010-11 Oberliga campaign, he led all scorers again: Richardson had 47.8 points per game, winning the Oberliga championship with Bodfeld.[6] Because of his high-scoring, Eurobasket.com granted him the title Best basketball scorer of the World.[7]
In 2011–2012, Richardson averaged 42.1 points per game for the Bodfeld Baskets in the 2. Regionalliga,[8] helping his team win another championship[9] which secured a spot in the fourth highest German division, 1. Regionalliga, for the following season. While at Bodfeld, he earned the nickname "Die Schwarze Perle" (The Black Pearl).[10] In 2012–2013, Richardson averaged 33.0 points a contest[11] and was named 1st Regionalliga North Player of the Year (by Eurobasket.com)[12] at the end of the season.[13]
In 2013, Richardson joined SC Itzehoe in the 1. Regionalliga.[14] He had an average of 28.0 points a contest for Itzehoe across the 2013-14 season,[15] earning him Eurobasket.com 1st Regionalliga North Player of the Year honors the second straight year.[16]
He played for Résidence Walferdange in the Total League from 2014 to 2017.[17] In the 2014-15 season, he emerged as the league’s leading scorer (28.7 points per game).[18] The following season (2015-16), Richardson ranked sixth in the Total League in points per contest (25.5).[19] In his third and final campaign at Walferdange, he pitched in with 25.6 points a game.[20]
In 2017, Richardson signed with newly promoted Gnúpverjar in the 1. deild karla.[21][22] He led the league in scoring, averaging 38.9 points per game.[23][24]
In May 2018, Richardson signed with Hamar.[24] He led the 1. deild karla in scoring again during the 2018–2019 season, averaging 29.7 points per game.[25] During the 2019–2020 season, he averaged a league leading 26.5 points per game,[26] helping Hamar to the second best record in the league. However, because the season finished prematurely due to the COVID-19 outbreak in Iceland, Hamar was not promoted to the Úrvalsdeild karla.[27]
On 16 April 2020, Richardson signed with Úrvalsdeild karla club ÍR.[28][29] He appeared in 22 games, averaging 18.1 and team leading 6.2 assists per game.[30]
After one season with ÍR, Richardson signed with newly promoted Breiðablik in June 2021.[30][31] In his Úrvalsdeild debut with the team, he had 27 points, 10 rebounds and 9 assists in an overtime loss against KR.[32] On 7 February 2022, Richardson scored 44 points in a victory against Tindastóll. It was the highest scoring output by any player in the Úrvalsdeild in the season.[33] Richardson re-signed with Breiðablik in April 2022.[34]
On 16 January 2024, Richardson signed with Haukar where he was reunited with Máté Dalmay, his head coach at Gnúpverjar and Hamar.[35]