Dj, do you know if this is a dual language release, or is it just in french?

Dj, do you know if this is a dual language release, or is it just in french?

Only French for now.

I wouldn't be surprised if it did. The original was in Japanese and French but got translated to English a few years later. I think it aired in 1986 in UK and USA. I hope the English voices are true to the originals, but that the translation is better.

Also, is this a direct sequel to the previous season ? Or are they somehow starting something new with the same characters, like a new quest or something ? I mean, do we actually have to have seen the previous season to understand this one ?

This is not really on the topic of season 2, but they have now started a manga version of the 1st season

http://www.manga-news.com/index.php/serie/Mysterieuses-citees-dor

It's made in France, but uses Japan manga style and so far it seems kinda nice. The only downside, though, is that they removed some story elements or moved them elsewhere into flashbacks (for example, the manga starts straight into episode 2 on the boat, with a flashback 10 years before where Mendoza saved Esteban in the sea, then later there is another flashback to episode 1, where Father Rodriguez dies and stuff), so the anime is definitively better. I guess they just tried to cram as many episodes as possible in one book (this one includes the first 7 episodes that were 20 minutes each) or they decided to put more focus on certain elements instead.

Indeed, although I think in Pokémon's case, the mangas came afterward too. In MCOG's case, though, one reason why the manga might not match up is because the 1st season of the anime was a co-French-Japanese production rather than purely Japanese, so it has plenty of European cartoon elements and fewer anime elements, like those scrolling backgrounds they use to create a speed effect. The Manga is purely French, but inspired at 100% from Japanese ones, so they tried to make MCOG less cartoon-ish in it.

Also you have to take in account that the anime was made 30 years before the manga, so they probably felt that some stuff needed to be moved around due to being less important or to remove long parts.