  Generalized dualities had an intriguing incursion into Double Field Theory
(DFT) in terms of local $O(d,d)$ transformations. We review this idea and use
the higher derivative formulation of DFT to compute the first order corrections
to generalized dualities. Our main result is a unified expression that can be
easily specified to any generalized T-duality (Abelian, non-Abelian,
Poisson-Lie, etc.) or deformations such as Yang-Baxter, in any of the theories
captured by the bi-parametric deformation (bosonic, heterotic strings and HSZ
theory), in any supergravity scheme related by field redefinitions. The
prescription allows further extensions to higher orders. As a check we recover
some previously known particular examples.
