Is there any good crossover fics between FoZ and FSN?
Hill of Swords There have
Hill of Swords been a few
Hill of Swords suggested, yes
Hill of Swords Hill of Swords Hill of SwordsHill of SwordsHill of Swords Search the thread for fate, FS/N, FSN, etc. There's a couple other ones that cross with FoZ that are decent, and at least one one other that's already been recommended here. As for Naruto/FSN fics, there
are some, but from what I remember most of them are mediocre at best. The lengthier ones, anyway. Same with bleach, though I want to say there's a couple better ones, there.
As for the
problem with FoZ in its natural form, it's a harem anime that... well, Louise is a malicious tsundere -- like, holy fuck what the hell are you doing abusive, in a number of cases -- and Saito is kind of a serious, grade-A letch, among a number of other things. From what I understand, the light novels aren't quite as bad, but the manga/anime, well. A number of the characters are either middling at best or outright unlikeable. For all the setting has provided a lot of fiction juice, and people have done some pretty amazing things with it, it is, in itself, not that impressive. Gets a lot better with only minor tweaks, yeah.
E: For the other ZnT/FSN ones I've read I would call "decent enough", check out
The Third Magic,
Void Bladeworks,
The Prince of Swords,
Miracle of Zero: Kingdom of the Forsaken, and
Why Me? Fair warning, Why Me? is the only one that's been updated in a while, and isn't
strictly speaking a FSN xover (just a heavily influenced multicross), and other than The Hill of Swords (which is awesome and you should read) none of them are finished, but... there you go.