They are two different talented players with different styles and skills; they can both finish because they are good at scoring goals.
This comparison is not proper in my opinion because Mbappe is a versatile player that can ply from the wing and also as a striker, while Haaland is a striker that cannot play as a winger; this means that Mbappe can play both wing and strike, while Haaland can only strike.
If I am given chance to chose, I will choose Mbappe because he is a player that can create chance and convert the chances while Gaaland can only convert a chance created.
People gives too much accolades to Haaland just because he was able to smuggle in treble in 2021, it was even more funnier when he was used to dragged Messi in the Balon D'or arguments but it's fine, PR doesn't create boundaries these days when people want to talk about football. Mbape isn't in the same league with Haaland even if he is converted from winger formation to striker formation, Mbape is going to do a lot better than Haaland who is always waiting for the right moment but Mbape doesn't wait.
It will not be a bad decision for any team that will have them both, it will only affect the players individual goals because any of them can score. I love them both because of their goal scoring mentality, if both of them can be in Madrid team, they can win any trophy just that they are both big too good defensively.
If Real Madrid buy Haaland, then the allegations against other clubs who think Real Madrid has bought the league will become true. Not saying it's not possible but it will be like Real Madrid are asking for much and I'm very sure Anceloti will decline such offer from the table if he is given the opportunity to come play, Mbape wasn't around this season when they win the Champions League, football will become boring.