It wouldn't work in practise though. Unless we play 2 up front but I think that's unlikely.
You could see yesterday that Mbappé went up a level when Giroud went off and he became the focus of the attack. Suddenly he was making runs that were being picked out, receiving the ball high and linking with others - that's what he needs, that's him at his best. You could slot a Lacazette in beside him and it'd be fine, he just wouldnt do much except bang goals in - the same thing Falcao does for Monaco. But we're a midfield team and that would leave us short where we need numbers to make our team work. On top of that, Wenger's just not going to do it.
Lemar also is not a top attacking midfielder. He's not creative enough, his touch isn't good enough, the weight of his passing isn't good enough, he doesn't have enough of a goal threat. I want him here because he has a lot of other good parts to his game but as a left sided midfielder/wingback, whatever you want to call it.
If both Ozil and Sanchez are leaving, and I don't think they are, then the only solution would be to buy Mbappé for whatever they want for him and give Dortmund the €85m they reportedly want for Ousmane Dembele. Easy!