Diversity of warp drive solutions is not in question in Trek: all sorts of folks fly in ships of all sorts of shapes. And the Feds don't limit themselves to nacelles, either, as is evident from ships with tucked-in coils (or at least tucked-in somethings) such as in the Defiant and Sarajevo - a very Cardassian approach to warp drive.
Klingon ships are all over the map as well. Even if we wish to bicker about how things went wrong when ST3:TSfS premiered, Klingons "nowadays" fly ships with and without nacelles, and the former come in a bewildering range of shapes.
That said, nothing forces us to think that the BoP would have its warp drive built into its wings. But "completely different line of tech" is probably still at play there, given the absence of anything looking even remotely like Kirk's twin cigars.
In comparison, the 22nd century BoP does have conventional-looking nacelles on the top corners of the odd shoulder grilles. And grilles shaped so that they make no sense as mere hinges for the wings, so they might just as well be warp "coils" or whatever. For all we know, this is a belt-and-suspenders version of something that in the 23rd century drops either the belt or the suspenders for affordability, or stealth, or insert-reason.
Timo Saloniemi