Rhetorical question: When was the last time an exchange amongst top clubs actually happened? (and almost doesn't count
)
In a nutshell, when you are dealing with the likes of DDG, Kroos, Varane (all Galactico class players), there will be no exchanges. Each player will command a transfer fee so large that it would send most clubs into administration.
I assure you, there will be no exchanges for DDG, Kroos or Varane. World record transfer fees on other hand, may be involved.
FWIW, Real Madrid already have an unbelievably good GK - Navas. A lot of you are behaving as if Madrid have already given up on Navas and bought DDG. IMO, Navas will continue as Madrid's No.1.