I think both Endrick and Arda Güler should leave the team on loan. Because they don't get any chances at Real Madrid. Even when Real Madrid is about to win a match very easily, Ancelotti doesn't want to put them in the game.
There are indeed some rumors that Arda Gulle is initially frustrated with the playing hours he has to play at Real Madrid. There are pros and cons.
On the one hand, he is in an elite Spanish club where it is not easy to get in, so using and being at Real Madrid is a pride.
But on the other hand, he is a football player, who certainly also wants to get good playing hours, to train and improve his skills, to make various shows of himself and his achievements. However, this is quite difficult to get at Real Madrid because of the many competitors who are superior to him.