Inter and Milan are in a mess as clubs mate, no better off in their respective leagues than us and both with bells as owners frankly, both have fallen a long way from where they where 5-10 years ago, he'd be exchanging one situation for a identical one (ponly with less prospects going forward)
Barca - not a chance in earth, all the strikers for god knows how long share one trait - being exceptional on the ball and with superb technical ability - Rom doesn't have that by a long shot - hes all about power and his pace mate
Madrid - possible - because they don't exactly follow common sense when buying players, then again is Lukaku as good as players theyve bought even recently who can barely get a start for them - Rodriguez for example, when you can buy any player in the world youi truly want - which Madrid can, then why would they actually go for Lukaku when he is not in the category of say a Lewandowski and not even as proven as say a Aubameyang?
Chelsea - weird one as it's the medias favourite love-child to link him too, but Conte has never in his management career favoured a player like Lukaku, he goes for the Costa type (hell he went with Pelle over 'better' strikers for Italy as he could do that hold up role he wants), IF they signed him - it'd be entirely the owners doing, a vanity signing much like Torres was for them or Shevchenko
United - Has Mourinho changed his opinion on the player - he's busted him out of one club before, whilst improved, Lukaku's game is essentially the same as it ever was as a player, yet again like with Conte, he isn't the style of striker that Mourinho has ever really favoured, both prefer the technical and back to goal players, IF they bought him its again a vanity signing for them rather than one that makes any sense for the manager, team and systems they play.
City - Guardiola - again another who favours a style of striker that Rom isn't and never looks like he will become
Arsenal - Unless they change owners they are never ever gonna spend 60m+ on a player, there summer is gonna be which sees there best players leaving rather than the other way around mate
In short - yeah their are some clubs that may come for him, but with every single one there is a huge question mark as to why they'd want him given the systems they play and managers prior choice of players in that role.
Only one i'd see as nailed on to want him would be PSG