Mane has been in stunning form for the Premier League leaders in 2019, scoring 11 goals in his last 11 games in all competitions at club level as the Reds challenge for glory on two fronts.
The forward is reportedly a top transfer target for Zinedine Zidane, with an overhaul apparently imminent after the coach's return to Madrid.
"He is ready [for the move]," Romeu told Marca of Mane.
"Madrid are a little weak in attack and he's the type of player that does a lot of damage in open spaces.
"He could help them reverse their current situation. He brings variation in attack, but he's not a prolific goalscorer like Cristiano Ronaldo, who goes well above [other forwards]."
Discussing Mane's attributes, Romeu added: "What I would highlight, above all, is his speed. He is a very electric and dizzying player. He has exceptional physical and technical qualities.
"At Liverpool he's grown a lot. This season, he's enjoying his best season in front of goal. I think he's acquired calmness and composure when finishing moves, either scoring or assisting. That is key."
Mane has 17 Premier League goals this term, as well as three in the Champions League.
He is considered to have worked on the end product in his game, with fellow countryman Salif Diao telling Goal: “If you look at last season when the Ballon d’Or list came out. [Mohamed] Salah was right up there, but Sadio wasn’t. And that was purely because of the goals.
“Salah was more clinical in front of goal, and that was why he got all the awards and the praise at the end of the year.
“I think Sadio recognised that, and you can see how he has used that this season. He’s more focused in front of goal, he’s more clinical, and that is making the difference.
"He has taken another step, and I think if he carries on this development then we will have a great chance to win trophies, big awards, and he will get the kind of recognition that Salah has had.”