I’m unsure about how should I handle this. I’ve added some releases to MusicBrainz that are recordings of traditional Brazilian nursery rhymes.
Since they are traditional songs, the lyrics and arrangements are unclear. Most people know by heart the main melody, but beyond that there are a lot of variations. Some songs I’ve learned a version in my childhood that is different from what my wife learned, for example.
Also, some recordings add intro that don’t exist on the original song. Since they are sung by children when playing, there aren’t any instrumental intros originally.
This is an example of something I added, and I added relationships to new works based on the originals to every song to reflect the arrangement, but I’m unsure if this is correct (or even needed).
I’ve searched in the forum for this question. I found this, but they are not handling exactly the same problem as I: Derivative works (mainly VG): Cover recording, or arrangement? - #6 by Silver_Skree
So my question is: when I’m adding a recording of a traditional nursery rhyme like these examples, should I create a work based on the original traditional song indicating the writer/composer of the adaptation, or should I only add as a cover recording?
EDIT: Clarity