I figured out this matchup, its still hard but this strategy is easy... Utilt collides with his aerial approaches from above like nair or dair and swats him away (even tho you still take the damage), ftilt stumps his ground approaches since he has absolutely nothing that outranges it, and fair will always beat him if he is approaching mid-ranged in the air. Fair > luigi's air game because it outranges everything he has unless he's approaching with a bair for some reason, otherwise it will collide with it. Of course there are other moves to worry about, but just be careful of them and use that basic rule. And as for bananas, he's immune to them, rarely use them. Pluck one at a time and just throw it at him dont bother so much about tripping him unless he is going to trip in place and not slide backwards. You can punish his trips with a dash attack though. Use lots of peanuts if he is far away too, and never go offstage unless you know whatever you're doing is going to work. Btw DI down, not up if he hits you with the fsmash otherwise you'll die at 70. If you can limit his options really well you're going to win.