Again, I'll point to the Tiki Supports. This time, her support with Robin.
"Perhaps because Chrom is not like Marth. He is much more direct, and committed to what he believes is right. Chrom might more resemble a different ancestor, from the age I was born in. Another great man in their line, from 1000 years before Marth... But the Marth of my time was wise and fair, and won hearts with his kindness."
So, again. Lucina is similar enough to convince the millennia-old dragon who actually knew the Hero King that she was Marth reborn. While Chrom reminds her of a completely different character (likely Anri, Marth's ancestor who first defeated Medeus).
While we're at it, look at the Lodestar class that is unique to the Marth Einherjar. It has the EXACT SAME look and animations of Lucina's Lord class. Which looks different from Chrom's Lord class, and has different animations.
I'm sorry, but in both gameplay and story, Lucina is a far more obvious Marth clone than Chrom is.
Yes, Chrom and Marth are different characters, counting Lucina. They all have their own personality, story, and purpose.
We're not discussing character here. Chrom is not Marth. Lucina is not Marth. Personality-wise, of course.
When I made that comparison with Marth and Chrom, I was referring to their physical traits in regards to SSB4. Marth in SSB4 is bulkier and more resembles Chrom's Awakening build.
Their arms, chest, and waist pretty much match up.
Lucina's arms are sticks. (And she's a pixel shorter than him, according to Sakurai.
)
The Marth in Awakening is canon to look like Marth's DLC artwork, which is why Lucina shares the same clothing and why Tiki mistakes her for Marth.
Yes, it's true Lodestar is a copy and paste of Lucina's lord class, all DLC/SpotPass are copy-and-paste and none are truly unique. But you can't ignore the canon cutscene which blatantly points out visually and with dialogue that Chrom and Lucina are practically the same type of fighter.
I agree with you that Lucina is far more obvious choice when picking a Marth clone since Sakurai states himself that the two share a big relationship, since Lucina literally poses as Marth. She has a reason to be included as a Marth clone.
I'm just disagreeing with you when you said that Chrom and Lucina don't fight the same way. They're literally doing the same exact moves in the cutscene. And that Chrom resembled Marth's SSB4 bulkier build more.