Codes do not allow trusses to be altered without the approval of an engineer.

Whatever method you end up with to correct the problem, it will normally need to be designed and signed off by an architect/engineer and would require a building permit in most cases.

That said, I would opt to simply replace the entire top chord of the truss with a new staight 2x4....(under an engineer's direction, of course).

Not that big of a deal. It would involve removing and reinstalling the gusset plates, cutting the nails which secure the sheathing with a reciprocating saw, some temporary bracing, and a single straight 2x4 of adequate length.

I do appreciate the thoughtful, serious response. That is a good solution. In this case, the roof pitch is 4 1/2-12 and the top chord is also the eave overhang. Also no way to get a 15' 2 x4 into that attic space from below. Replacing the top chord would have to be done from above after removing the sheathing. Still weighing the (very limited) options.