Well, according to my research is
Ana the Spanish variation of
Anna, also applies to
Ania.
Anna is the biblical and Greek form of
Hannah, meaning grace.
Anne is the
German, English and French form of
Anna, for
Ann only the English way.
Mixed forms are Annabarbara,
Annabeth, Annalene, Annalies,
Annalisa,
Annamaria, Annamarie, Annarösli (Swiss).
Respectively Annebarbara, Annelene, Annebärbel, Annedore, Annegard,
Annegret, Annekat(h)rin, Anneli(e)s(e), Annelore, Annelotte, Annemarei, Annemargret,
Annemarie, Annerose, Annetilde & Annetraud.
It makes no difference for me, like both spellings, pronunciation/diction ultimately in the same way. Agree with you, would probably again and again write
Anna, automatically.