I don't think Klopp wants to consider Lukaku because Lukaku seems not suitable with Liverpool game style. Liverpool is looking for a typical player that has a similar characteristic as Mane and Lukaku is clearly not the right option. Nunez is a good option to replace Mane's role in Liverpool squad although his transfer fees are quite expensive. And Nunez is still a young player who can play a long time.
Lukaku is a good player but the EPL is not a friendly enough league for this player, how many clubs has he been to and only at Everton did he play well but for big teams like Chelsea and Manchester United he can't do much there.
His vision of the game doesn't really match Liverpool, why should it be forced, even though in this case Liverpool still have many options for attackers but I don't think Klopp will make a choice for him, especially for Nunez, soon the contract talks will be completed.
If there are rumors that say that Lukaku will join Liverpool, I will not respond to these rumors, because Lukaku is not the type of player that Jorgen Klopp wants, because Jürgen Klopp only wants players who can move and can run after and pick up the ball, according to I think Lukaku is more suitable to play in the Italian league, because the pattern of the Italian league game often applies one or two games and is not too draining like the English league,
Most likely Lukaku will rejoin Inter Milan.