This is certainly a Spanish printing written in Castillian Spanish, and with the Spanish price in Pesetas. Are you saying that the original production, storywriting and artwork was done in France? The only credits I see (Sanchis and Ortiz are Spanish, rather than French surnames, and the fact from history is from the history of Spain. The uploader also has a Spanish surname (Sanchez). I'd bet that this book was produced in Spain for the Spanish market.
I see that you are correct that this book was misfiled, as it doesn't show up in The Spanish Language Books Section of CB+, which is listed as where it is filed, and provides a link to the section.
Link to the book:
El club de los cinco - almanaque