Luci’s swordsmanship is influenced by not only her father, but Lon’qu. Lon’qu may have never formally trained her as her father did, but from a young age she recognized his skill and often hid to watch him train. Her swordsmanship is incredibly similar to her father’s, yes, but there’s a sharp, quick, precise brutality to her strikes that is reminiscent of her time observing Lon’qu as a child. It was why she could defeat him in the arena, remembering how he carried and utilize his blade from before. Even then, with the way her father taught her to fight, already a skilled swordsman, the two techniques melded into one. Though Luci does err towards her father’s way of handling a blade, should one watch her wield it, they might notice traces of different techniques that Chrom does not utilize.