I have read so many novels where MCs start using the sword and train it. But as progress it gets more and more sidelined. I am looking for novels where the user focuses on improving his sword technique/art. Like in 'Seeking the flying sword path'. Where the MC focuses on becoming stronger with/through his sword way. Fanfictions/Originals/Light-Novels are all accepted.
If you are okay with manga, then you really should read "Ares". This hidden gem is really underrated and deserves much more attention, even if you aren't into swords. EDIT In fact, I will reread it right now Thank you, that I remembered this awesome manga because of you.
Nine Star Hegemon Body Art - his unique cultivation method is body strengthening, but his primary fighting method is with a heavy saber. There was only a brief mention of him learning a generic sword style, but he really just swings his saber around with brute force. He does fortuitously pick up a incomplete manual for a named saber skill, but it only has the 1st move. He relies on this one move as his finisher for hundreds of chapters (3-400? I can't remember) before he gets the 2nd move. Much, much later, he finds and gets accepted into the sect that originated this saber skill and is taught the higher moves. While I haven't read many cultivation novels, I find that most other cultivation novels replace their MC's entire repertoire every time they rank up. With this story, even as MC adds to his abilities as he progresses in realms, he continues to use his old skills. Of course the old skills gradually get weaker compared to the power creep of the foes he's up against, but they are still relevant if only because they're cheaper to use on the cannon fodder in terms of Qi and spirit requirements.
You could read Against the Gods ... Well, you probably know about it, maybe. But it is quite interesting how the protagonist develops after getting a heavy sword (although it takes a while before he does). After he gets the first heavy sword, he goes through a few more until he reaches a definite and well OP sword that evolves according to certain circumstances. The sad thing, however, is that although the protagonist uses the heavy sword a lot and is his main form of combat from a certain point in history, he does not delve much into the sword itself. Like those plots "intent on the sword" or "the path of the sword".
1. Eternal Reverence (no harem) 2. Dominating Sword Immortal (two wives) 3. Sovereign ascension (harem,. Not sure) 4. Sword god ( 14 chapters translated currently not translation available it's good) Please reply if you know more sword mc novel focusing more on cultivation than harem