Zouma was really good two seasons ago when we had a terrible season, and cemented his place in the starting eleven. Then he had that knee injury against United and it took him almost a year to return to full fitness. By that time Conte took charge switched to a 3-4-3 and trusts the back three too much to rotate them. I'd keep him for the new season and i think if he does get loaned he won't be returning.
As for the Hazard injury, he will miss the qualifiers, the pre season and most likely the few weeks into the new season. If Real was really going to offer 100mill then this is a disaster because he is nowhere near worth that kind of money, i would take it tough.