It's very hard to see Man U letting Rooney go to a premier league rival, but I wouldn't entirely rule it out. To make it happen, Chelsea (or another club) would have to offer over the odds, or provide some other incentive (player), otherwise Man U would just attempt to offload him to somewhere like Monaco or PSG.
It's hard to see this as the work of reputable journalism, when the original Mata/Luiz story seemed to come from no-where. Definitely just looks like someone has gone back through all the rumours this summer and gone:
Rooney unhappy at Man U - check
Jose a fan of Rooney - check
Man U after creative midfielder - check
Jose not a fan of Luiz/Mata - check
Potential swap rumour on the cards - check