  We study the 3-point functions of gauge-invariant scalar operators in four
dimensional $\mathcal{N}=2$ superconformal quiver theories using supersymmetric
localization in the planar limit of a large number of colors. By exploiting a
web of nontrivial relations, we show that the 3-point functions can be
expressed in terms of the 2-point functions through exact Ward-like identities
that are valid for all values of the coupling constant. In this way, using
recent results about the 2-point functions, we are able to obtain the
asymptotic strong-coupling expansion of the 3-point functions and of the
corresponding structure constants in the planar limit. Our results extend to
sub-leading orders what has been recently found at leading order, where a
precise match with calculations within the AdS/CFT correspondence at the
supergravity level is possible. Therefore, our findings can be interpreted also
as a prediction for the sub-leading string corrections to these holographic
calculations.
