If your opponent is a roll dodge, dins fire, smash spammer.... Then yes, you will have a difficult time. If you can sh homing missile cancel properly, you should be able to shoot faster than Zelda can use dins fire. I can't help but think, if your opponent is adapting to your playstyle, shouldn't you be doing the same for their playstyle? If the same strategies don't work, switch things up. I would approach with homing missiles and zairs, depending on how far away I am from Zelda. After that, I'll punish whatever action my opponent takes.
If Zelda:
rolls backwards- she's closer to the edge now, keep zairing/homing missile cancel
rolls forwards (in front of you)- instant dash attack>jab>screw attack, or whatever combo you want. check out jasona's vid, "she only gets better" for some combo ideas
rolls forwards (behind you)- if she's right next to you, screw attack. if she isn't ftilt. if she's too far away for ftilt, dash away from zelda and restart your approach
side steps- if you're in range, ftilt. if not fire a missile (on the ground if you have to) super or homing missile, it doesn't matter. heck, you could even charge shot. it should force her to avoid it, after which you can try punishing.
jumps- follow her into the air with uair or fair. if she double jumps to avoid it, try attacking her as she falls back down. uair and fair all have long lasting hitboxes that should hit her out of an airdodge if she attempts it. you can even use screw attack to switch things up.
jumps with an attack- let her attack finish, shield if you have to. shield+screw attack if she tries to hit you with the attack. if she's just trying to space, try hitting her with another zair or aerial if you're close enough (after her attack is done)
shields- she can roll dodge out of this, so don't try to grab unless you are absolutely sure it won't miss. try to jump and dair her. use it so that when your attack lands, you will land behind her. this way, you can't be punished by her grab.
gets hit- keep approaching if you're too far away, otherwise, start a combo!!
pardon my dumb mechanical errors... I was too lazy to correct them... I had a long day =/