Real Madrid will probably experience a slight change because of three of the madrid players like marcelo, isco and bale. Although these three players are rarely seen, at least Marcelo and Isco participated in half of Madrid's matches last season.
And for Barcelona I corrected a bit because they weren't aggressive in signing players this season, there weren't even any new names besides a few loan players, right?
To be fair, how much did they really play? Bale didn't play at all, Isco didn't neither too many times I believe, and maybe Marcelo was the only one who had some. Marcelo played about 800 minutes, on 17 games. Isco played 400 minutes on 17 games as well (mostly last minute bench subs), and Bale had under 300 minutes with just 7 games. So all of them combined do not have as much as one starter, all three totals.
This is why I think these three leaving means absolutely nothing at all. You could literally get some youth team player at age 17 and put them on this bench duty and they would be able to give the team at least this much. Hence, I believe that it doesn't change anything for the team.