Diccionario de Nombres de Personas by
Jose Albaiges Olivart lists Elano as another Spanish form of Helanio/Helena. Usually names ending in -o in that dictionary are simply assumed to have feminine forms ending in -a even when those are not directly listed, so I guess Elana must be considered another Spanish form of
Helen.
Smadar Shir Sidi's
The Complete Book of Hebrew Baby Names does not list Elana as a form of
Ilana, but I can certainly see how parents in English speaking countries would be tempted to respell
Ilana as Elana, since the pronunciation of the name is "ee-LAH-nah".