A bit on the weaknesses of Darwin Nunez:
He's very promising but there are a few red flags that make you question that price tag.
On paper he looks great with goals against Ajax, Bayern, Barca and Liverpool at 22 and with 32 goals in all competitions; his movement is decent, he's tall, strong and quick.
On taking a closer look, some cracks in the facade appear:
Firstly, a major red flag(especially if you're a high possession club) is his incompetence in possession. The other day I saw an article in the Athletic where Smarterscout rated his Ball Retention Ability a 2 out of 99 when adjusted to Premier League standards. Regardless of these graphs and stats, I'd say that he's pretty suspect in possession.
His passing is not upto the mark for the top clubs who prefer strikers who are good at link up play. Only completes 11.7 passes per 90 in the Portuguese League. Bottom 10% among forwards in top 5 Leagues of Europe. 9 completed passes per 90 min in UCL. Pretty average pass completion percentages everywhere too.
Nunez has a tendency to get caught offside. Despite his game being largely based on running in behind like your Haalands and Vardys, he doesn't always time his runs well. Ofcourse this can improve with age.
The worrying thing is how he'll perform against low block teams. He's brilliant in a pure counter attacking team with his speed, physicality and directness in transition(hence so good for Benfica in CL) but Ten Haag prefers a different style of play.
Along with his technique, his decision making can be sloppy at times. Often releases the ball in the wrong moment especially after decelerating.
Despite being 1.87 m tall and strong, he doesn't use his body well and has weak hold up play. Only wins 1.1 Aerial Duels per 90 min with a Aerial win % of 35.
A lot of it points to the fact that he isn't really a lone striker. His heatmap shows he loves to drift down the left channel and is best used in a strike partnership.
Lastly, since 2017 he has had 3 major knee injuries.
All in all, I think he has quite a few weaknesses and red flags to justify his huge price tag. He's not a very sureshot/guaranteed success at a big club. I think due to the lack of great attacking options in the current market, he's being rated higher than he should be.
We have all seen Darwin's strengths and great qualities but this transfer will still be a massive gamble imo. Personally, I'd rather get Nkunku.