Somewhat... late/necro but... For this matchup... I generally use Marth's movement and speed to full effect. Dash dancing/wavedashing to bait out Naryu's Love is what I usually go for. The endlag of that attack is stupid ridiculous. You *almost* have time to grab a cup of coffee, come back, and then punish. From there just give her that tip, tip, tip. And don't forget to ease up if chasing her in tumble. It's easy to get greedy and mistake her for being stuck helplessly in hit stun when in reality, your opponent is waiting for you to try to continue comboing so they can give you that good old star foot. (You can also bait the sh*t outta that) They'll usually follow that up with Din's Fire since she's too slow to chase usually, depending on your percentage. Marth can bob and weave through these easily... and cut through them like butter (?) with his sword.
From a neutral position I also try to bait out the twinkle toes, cause, once again, you know they're gonna go for it pretty frequently. Good spacing gives you an easy punish for any whiffed feets. Follow through with some BnB's but the key is to learn when to back off. Trading with the feet is no bueno for Marth cause it will usually knocks you back far enough for her to set up a defensive zone.
Basically... play a more... cautiously aggressive game against Zelda and you can't lose. Oh and teleports for Zelda give her a bit of extra mobility. They allow her to pop in on your waving and the dashing of the dancing pretty easily. So be mindful of that as well. And with her being able to air dodge out of it from the ground, she has extra options to get in on you. Generally it's not a huge deal, but just something extra to be mindful of.