Kean is owned by Everton, loaned with no option. It will be up to him to decide I case we try to bring him back. IIRC he already chose PSG instead of Juve last summer, so I wouldn't count on him not choosing to stay at PSG.
Aguero was dream signing since Atletico M. days. But now is not the time for him in our jearsey, to bad this transfer wasn't possible couple years earlier.