Nineteen-year-old striker Biereth arrived at the Emirates from Fulham's academy last summer and enjoyed a strong campaign at Under-23 level under Kevin Betsy.
Biereth ended his first season at Arsenal with 12 goals and five assists in 26 outings for the young Gunners, including 11 goals in 21 Premier League 2 matches.
The Denmark Under-19 international came up with a hat-trick against Chelsea and a brace against Manchester City in league action, while also captaining the side in their final three matches of the season.
First-team manager Mikel Arteta did not hand Biereth his first-team debut last term, but he made the bench in the Premier League, FA Cup and EFL Cup.
Instead of integrating Biereth into the first team with Europa League football to come next year, The Athletic reports that the teenager is instead due to join RKC Waalwijk on a temporary deal.
The report adds that Biereth could then be loaned out to an English club in the 2023-24 season, and he is set to be joined in the Netherlands for the next 12 months by Rekik.
The 20-year-old - a previous prospect of Feyenoord, Manchester City, PSV, Marseille and Hertha Berlin's youth academies - signed for the Gunners in a £540,000 deal in January 2021.
Rekik also featured regularly for Betsy's side in 2021-22 with 16 appearances in all competitions - 14 of which came in the Premier League 2 - and he made a pair of outings in the EFL Trophy.
Rekik provided one assist for the Under-23s last term and also captained the side on one occasion against Tottenham Hotspur, which ended in a 2-1 win for Arsenal's prospects.
The centre-back has already earned three caps for the Tunisia national team and made two substitute appearances at the Africa Cup of Nations earlier this year, and he is understood to be heading for Sparta Rotterdam.
Rekik is pining for a spot in Tunisia's squad for the 2022 World Cup in Qatar and will hope that regular first-team action will aid his bid for selection to the team.
Arsenal have already added one young prospect to their ranks in the form of 19-year-old Marquinhos, who could potentially work with the Under-23s next term or be loaned out to continue his development as well.
Fabio Vieira and Matt Turner's arrivals from Porto and New England Revolution respectively should also be confirmed in the near future, while Leicester City's Youri Tielemans remains high on Arsenal's priority list.
The North London club are also said to be hopeful of concluding a £70m double deal for Ajax's Lisandro Martinez and Manchester City's Gabriel Jesus in the coming days.