Real Madrid needs a good player to replace Modric and Kroos. Every team knows that and they will try to prevent Madrid from having a good midfielder or simply increase the price of the specific positions that Real Madrid are thirsty for.
I doubt PSG will sacrifice any of its good player because it has a good squad, they might add more players, sell those who aren't that useful but certainly will not allow these useful and having a contract for more than a year.
Real Madrid's midfield is in need of a player who can be the heart of the game. There used to be Kroos and Modric, but both can be said to be no longer at Real Madrid. After Kroos retired, Modric next season already belongs to AC Milan.
Only Valverde, Jude Bellingham and Tchoumeni.
Trying to get a new midfielder for me is important for Alonso, but for now don't focus too much on that. Trying to utilize the existing players while continuing to monitor the targeted players is better.
Arda Guller isn't primarily a central midfielder, but under Xabi's tutelage, he can do a good job in that position when Alonso wants him to.