VelvetViolet
Adventurer
Urban Shadows doesn’t really have a setting. It has a bunch of playbooks, but not much in the way of setting books.I'd suggest virtually any dedicated urban fantasy system will have some degree of setting assumptions baked in. If you want to avoid that, I'm back to suggesting finding a generic system that handles at least moderate levels of power well and going that way (as Danny above obviously is considering).
Night Shift has four separate campaign settings in the core rulebook. They’re basically kitchen sink urban fantasy setting #1, kitchen sink setting #2 (not sure why there are two of these, I couldn’t tell the difference), post-apocalyptic setting with supernatural monsters, and a magic school setting.
d20 Modern had distinct writeups for “Shadow Chasers” (Buffy-style monster hunting) and “Urban Arcana” (D&D monsters and races end up in contemporary Earth, hidden by the veil of Shadow).
Aside from that, I got nothing.