According to the link in my post, they throw away the heart of the story and added a lot of fluff, including 'The Little Mermaid' elements, in order to get a full movie out of it, (e.g. a bullying backstory on Jaskier.) Whether the mermaids are similar, I don't know.

According to the link in my post, they throw away the heart of the story and add a lot of fluff, in order to get a full movie out of it, such as back info on Jaskier. Whether the mermaids are similar, I don't know.