Endo only joined Liverpool last summer from Stuttgart for a reported £17m and was identified as a transfer target after the Reds missed out on signing Moises Caicedo and Romeo Lavia, who both completed big-money moves to Chelsea.
Nevertheless, the 31-year-old featured regularly under former manager Jurgen Klopp in his debut campaign at Anfield, making a total of 43 appearances across all competitions.
Endo primarily operated in his favoured deep-lying midfield role for Liverpool and faced competition from fellow new recruit Alexis Mac Allister for regular starts.
Following the arrival of new head coach Slot, Endo now believes that the Reds should look to bolster their midfield options further, even if it means that his game time is reduced next season.
Endo welcomes midfield competition at Liverpool
Responding to reports that Liverpool are planning to sign a new midfielder during an interview with ABEMA Sports Time, Endo laughed and said: "I don't care about those reports, but I also think it would be better to get the number six midfielder.
"I think there is a possibility that they are viewing a number 10 player [Alexis] Mac Allister as a number six/anchor, but at the moment there aren't many number six players to begin with.
"I had the most opportunities to play, and so did Mac Allister. We also had Thiago Alcantara, but he had a lot of injuries and is set to leave the club at the end of this season. We also have [Stefan Bajcetic] but it's still unclear as to whether he will be able to contribute immediately.
"Considering my age, I think it might be okay for me to get the number six. But if it ultimately makes the team stronger then I'm all for it, because there will be competition and I just have to win my position again. So I'm not really worried about it, and in fact I think it might be okay if I win."
Slot in regular dialogue with new chief Hughes
Slot, who has moved to Liverpool from Feyenoord, does not officially begin work with the Reds until July 1, but he has already been in regular dialogue with new sporting director Richard Hughes about preparations for the 2024-25 season.
Speaking to Liverpoolfc.com, Slot said: "I think now is a good moment to arrive here and talk to you, but let's be clear: I don't start today, I've been in a lot of contact with staff members already - from people who are working here to the new staff members that are coming in - and, of course, almost every day Richard [Hughes] and me are calling each other because we have to talk.
"This is also a very important phase for the new season, to make sure the team is ready, and we have to play in the pre-season."
Liverpool have been linked with a number of midfielders from across Europe in recent weeks including Juventus' Adrien Rabiot, Bayern Munich's Joshua Kimmich, Monaco's Youssouf Fofana and Atalanta BC's Teun Koopmeiners.