Mayweather was a 50-0 boxer himself who came out of retirement earlier this year to fight UFC superstar Conor McGregor, whom he beat.
The American is one of the most financially successful fighters of all time and believes if Joshua wants to maximise his own profit, he should stay in the UK for his proposed unification fight against Wilder.
“I think it can happen in the UK,” Mayweather said.
“I think it’s bigger money in the UK.
“That’s just how I feel.
“I think everybody is overlooking Anthony Joshua.”
Joshua’s last fight saw him beat Carlos Takam at the end of October, after which promoter Eddie Hearn outlined their plan to unify the heavyweight division by fighting Wilder and WBO champion Joseph Parker.
Both fighters are unbeaten but Hearn appears to have made more progress with Parker’s camp and that bout is expected to be announced for the end of March; Wilder meanwhile admitted he will wait for Joshua.
But while Wilder felt he sent a message to the boxing world with his spectacular first-round knockout of Bermane Stiverne, Mayweather disagrees.
“We look at Deontay Wilder’s last fight,” Mayweather added.
“He did what the f*** he’s supposed to do in great fashion but when you look at the guy he fought, the guy was like 6 feet and 40 years old?
“You gotta realise Anthony Joshua showed the heart of a lion.
“[He] got hit by one of the Klitschko brothers – got right back up and showed the heart of a lion.”