HI Juan Manuel,

you are absolutely right. There are many things that should improve in the LaTeX exporter and simplifying language treatment is one of them. What I show in my example is how to circumvent all the limitations in the exporter and give a working example for people who need it. 

 Adding AUTO to latex_class_options would be extremely helpful, since then you can load babel indicating the main language only and even avoid the PassOptions and can live with \usepackage{alphabeta} only.
This is a MWE for mixing German and Greek which I use to compare with what org-mode generates:

---cut---
\documentclass[greek,ngerman]{scrartcl}
%% \documentclass[greek,ngerman]{scrreprt}
%% \documentclass[greek,ngerman]{scrbook}
%% \documentclass[greek,ngerman]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[ngerman]{babel}
%% \PassOptionsToPackage{main=ngerman}{babel}
\usepackage{alphabeta}

\begin{document}
Ach, unsere Freunde die Griechen: \textgreek{νους} (mit \verb|\textgreek{}|).\par
Ach, unsere Freunde die Griechen: νους (direkt im Text).
\end{document}
---cut---
The commented document classes are all I had the time to test.

Best, /PA


On Sun, 21 Jan 2024 at 18:47, Juan Manuel Macías <maciaschain@posteo.net> wrote:
Pedro Andres Aranda Gutierrez writes:

> +#+begin_example
> +,#+latex_class_options: [greek,spanish,oneside]
> +,#+language: es
> +,#+latex_header: \PassOptionsToPackage{main=spanish}{babel}
> +,#+latex_header: \usepackage{alphabeta} % to support greek script
> +#+end_example

I think this example doesn't take advantage of the AUTO facility, which
is what the section is about. Btw, maybe it would be nice to extend ''AUTO'' to
latex_class_options and \PassOptionsToPackage? Something like:

#+latex_class_options: [greek,AUTO,oneside]
#+language: es
...

However, I would only find the \PassOptionsToPackage command useful in
classes that already load babel with a main language. From Org, using
just pdfTeX, I think it would be simpler:

#+language: es
#+latex_header: \usepackage[greek,AUTO]{babel}
#+latex_header: \usepackage{alphabeta} % to support greek script

or this variant, using babelprovide and an INI file:

#+language: es
#+latex_header: \usepackage[greek]{babel}
#+latex_header: \babelprovide[import,main]{AUTO}
#+latex_header: \usepackage{alphabeta}

Best regards,

Juan Manuel




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