To everyone reading the thread this is what they mean.
They are an indie publisher that offers to publish your stories to different sites and if needed help get paperback copies made.
They do not pay you anything upfront. The 40% is what you get for using them as publishers. What happens is they will publish your work on sites and you make 40% of any profit made.
The 60% they take is based on them providing access to certain sites, handling paperback distribution, and translating to French. They are more focused on selling in French and therefore you can probably keep the rights for other languages.
I have talked with them before and the posts they make can be misleading. Not by any malicious means but I believe the language barrier is making it hard.
When they say they are looking for shojo/josei, they are looking for Mangakas to create new stories in this genre and use them as publishers.
Similarly for the “2 artists, which one is already known by Japan readers” they mean they have two artists as clients who use them to publish into the French mangaka scene.
Feedback To OP.
I would work on drafting a more communicative message that explains who you are, what you do, what you offer, and break down the pricing. I’ve seen a couple of your posts and it would do you and the community well to have a more clear request.
This message I wrote is not to discourage anyone from working with OP but to help them understand and I wish everyone the best of luck on their ventures.