The young striker is reported to have penned a 5-year deal at Vicarage Road.
He is joining Watford from Rochdale AFC in the second tier of English football.
Baah was born in Germany to Ghanaian parents, but was raised in South London and spent four years in Crystal Palace's academy from 2013-17.
He joined Rochdale in 2019 after a brief spell with non-league side Whyteleafe.
2025-01-08T10:53:13+00:00 Accra Hearts of Oak head coach, Aboubakar Ouattara, acknowledges that every game is challenging, given the team’s rough start to the season. 2025-01-08T15:34:39+00:00 Former GFA Communications Director Ibrahim Sannie Daara expressed deep frustration after watching highlights of Dreams FC's 1-0 win over Accra Lions, citing biased officiating by referee Maxwell Hanson. 2025-01-06T11:02:11+00:00 Hearts of Oak beat Legon Cities, Asante Kotoko held Medeama SC to a stalemate, and Bechem United defeated Hearts of Lions—GPL match week 16 round-up. The teenager was named EFL Young Player of the Month for January after scoring a stunning brace against Charlton Athletic.