The 23-year-old Dutchman, who spent a brief stint at Town between February and March 2016, has signed a two-year deal after struggling to force his way into contention on the South Coast.
Since signing from Dutch giants Feyenoord in August 2015, the winger managed just 17 appearances for the Seagulls and also spent time on-loan at Dutch side Go Ahead Eagles last season.
Meanwhile, Leicester City are hoping to complete the signing of Kelechi Iheanacho from Manchester City later this week, according to The Leicester Mercury.
A £25m deal is thought to be close, with negotiations agreed 'in principle' after the forward was deemed surplus to requirements at the Eithad Stadium by manager Pep Guardiola.
Overall, the 20-year-old has scored 21 goals in 64 games in all competitions since making his debut for the Premier League giants in 2015 but made only nine starts for the club last season.
According to The Telegraph, the Austrian forward spoke to Stoke boss Mark Hughes last week when he informed him of his desire to leave.
Although the Potters are reluctant to sell, they are bracing themselves for an improved offer of around £20m with the Hammers seeing the player as essential acquisition this summer.
Another Austrian looking to leave their current club is Tottenham Hotspur's Kevin Wimmer – according to The Mirror.
The 24-year-old has revealed he wants to quit North London for Southampton in search of regular first-team football after playing just 15 league games since signing from Cologne for £4.3m two years ago.
The Lancashire Telegraph are reporting Burnley FC are looking to bring Swansea City's Jack Cork back to Turf Moor.
The midfielder featured 57 times for the Clarets in two loan spells in 2010 and 2011 and he could be set for a return with talks understood to be on-going over a potential £10m deal.
The 28-year-old has just a year remaining on his current deal at the Liberty Stadium with his place looking to be under threat next season as boss Paul Clement continues re-building a side which flirted with relegation last term.
And sticking with Swansea, the club have slapped a £50m price tag on Gylfi Sigurdsson with the Icelandic playmaker heavily linked with Everton and Leicester.
The Guardian are reporting the Swans remain determined to keep hold of the player who was named the club’s Player of the Year for the second successive campaign last season.
Sigurdsson has three years left on his contract having signed a new deal last August and has scored 30 goals in 112 games since signing from Tottenham for £6.8m in July 2014.