Haaland and Mbappe are two different players with different playing styles. I don't think Mbappe is a pure center forward, while Haaland is a pure center forward. Mbappe can dribble like a winger, while Haaland is a typical finisher who tends to wait for a pass. Mbappe can play on the wing and center forward, while Haaland cannot.
I don't expect a scenario where Haaland and Mbappe are on the same team in the future. This is not a good choice for any team because after all they are both competitors in the current era. Both are productive center forwards, but I prefer Haaland as a pure center forward over Mbappe.
I won't rule out the possibility that they will play together in the future, but for now I think they will continue to play at the clubs they currently play for, Haaland at Manchester City and Mbappe at Real Madrid. I wonder, why do some people expect them to play together? Isn't it more interesting when 2 young players who have very good abilities are at different clubs? I even hope they will become rivals in the same league in the future, for example El Clasico or the Manchester derby for example. Lol
This reminds me of Ronaldo and Messi, who until now have never played for the same club. Even though many people want to see them at the same club at the end of their careers. But that doesn't seem to be happening and they will never work together at the same club. Same with Haaland and Mbappe, although these are clearly in different situations.