IMO MB shouldn’t manage those links (possibly varying in time when rights are sold or when they fall in the public domain).
Official DB already do list who to send the royalties to.
It often is contradictory with how the credits are artistically listed in the releases (what we want).
A band would often want to not reveal who did compose and who did author and would then list the band name on most their tunes. Same goes with pen‐names. These are an intent that is followed in MB, isn’t it? 
Royalties collector/managing societies (JASRAC, SACEM, etc.) may have to replace pen‐names by identities or to split this credit into each band member so that they each get equal share of the benefit (which was also intentional in the first hand, IMO).
We shouldn’t set these kind of credits because it would almost always be wrong to say that each member did participate in both the lyrics and music. That’s not for MB, is it? 