Di Maria was dog shite and couldn't knuckle down any spot he was put in. Quite often he was given a go on the wing and couldn't complete 5 yard passes. Best saved for a di Marian thread, but my point is he was shite regardless of position.
Your examples are a bit bizzare. Deubachy was the only right back cover for Arsene and as such was required as a fall back. Morata was vital to Reals league success, he won most points for any club behind Leo Messi. Again, they would rather not sell him as he's an important player for th
em.
Chelsea will come around and do business if it comes to it, I don't see it happening this summer. They've had direct title rivals strengthened by seeing a top target stolen from under their nose. They will hold on to a good player to avoid strengthening them further.