Hi Fifi
I find very interesting your idea of different sections for different languages. It makes easy also adjourning the PDF appending the new language to the file.... also if I was thinking what it'll happen if the languages become too much.... I must evaluate the best way to get a shrinked result with a large amount of languages.
About
what PDF editor do you recommend and on what OS
I very often use Windows 10 , the file posted has been built using OpenOffice text editor and screenshots pasted into MSPaint.
.... if I want a document with a more dinamic structure I must think to a program that show help after the user has choosen the language of interest OR to a HTML file with CSS OR JavaScript.
Welcome feedbacks