The latest bizarre transfer rumour to rise to the top of the pile this summer is Wolves' supposed interest in Atletico Madrid striker Diego Costa.
The former Chelsea man endured a dreadful

More fuel was added to the fire following the 'comments' of Costa's controversial agent Mino Raiola, who was quoted saying; “Diego has had many offers to return to England but only one stands out."
And Jorge Mendes hasn't said anything about an offer from England.
— Sport Witness (@Sport_Witness) July 9, 2019
Not sure if this some kind of media experiment or just usual bullshit. Either way, it's bullshit.
Sport Witness have revealed that the rumour has genuinely been plucked from thin air as Globo Esporte have never even reported on the matter.
What's more, there is no evidence to suggest that Raiola has made any comments regarding the Atletico striker's future, so it can only be assumed that the quotes have been entirely fabricated.

Everton have also been cited as a possible destination for Costa this summer, but those rumours were also shot down by Jim White, who told Talksport, as per The Express:
“You can forget that…that has been described as complete nonsense.”
It may be safe to assume that no one is actually that interested in Costa right about now.