No one can doubt that Mbappe is a good player and he'd improve the squad of the Gunners but I don't think Arsenal needs such a player RN. He's got a self-centered mentality and I doubt he'd be able to fit in the team. What Arsenal needs is not just any kind of forward, but one who would be willing to share chances when he's not in a position to score, not a childish player who stops putting effort the moment he does not see the ball.
Apart from that, I also don't see rumors about Mbappe going to Arsenal from PSG and I also think that Mbappe is really not suitable for Arsenal. Because Arsenal need more players who can work together and don't blame each other and give vent to their selfishness on the field so that a typical player like Mbappe is slightly less suited to the character of the Arsenal team and for now I actually have more confidence in Mbappe who will stay at PSG rather than leave to another team.