I'll be honest, I hate Twilight with extreme passion for many, many reasons, but I'll say this; Instead of blind, random hate, I actually have reasons, examples, and actually am reading the books so I'm not following the bandwagon of ''This suck because sparkly fairies". I despise the author, the main characters and the incredible lack of plot, but I enjoy reading it because I get to laugh and rage, which is probably some sort of ''I love this for all the wrong reasons'' kind of love, but oh well.
A touhou rewrite? Sure. That removes the 3 things I hate the most about the series. Hell, Twilight was full of amazing potential that was pissed on shamelessly and re-writing it is something that has been done by many people, and usually, made the story great.
Your character switch is actually pretty good, though I majorly disagree with Emmett - Meiling. The martial art and physical strength thing matches up, but the personality are insanely different. Yuugi/Suika might work better, seeing how they're a lot more carefree and less stuck up than most people, which is kind of what Emmett was in Twilight.
But really, on a rewrite-unrelated note, I think anyone who hates the books only because there are "Sparkly vampires" just hasn't read it. Plus, your assumption as to why people would dislike the book are somewhat presumptuous. The Cullens are far worse than Dracula anyway; He didn't try to put up a bullshit noble-like pride and pretend he's perfect. Plus, he only wanted his loved one back, in the end.