  We give another proof of the existence of the endoscopic transfer for unitary
Lie algebras and its compatibility with Fourier transforms. By the work of
Kazhdan and Vashavsky, this implies the corresponding endoscopic fundamental
lemma (theorem of Laumon--Ng\^o). We study the compatibility between Fourier
transforms and transfers and we prove that the compatibility in the
Jacquet-Rallis setting implies the compatibility in the endoscopic setting for
unitary groups.
