People who help in the transmission of a message, for example reporters or copy-editors, are known in media circles as

People who help carry a message onward, such as reporters or copy-editors, are known in media circles as relay people.

They pass and process the message along the chain from source to audience without being its original author.

Calling them carriers wrongly reduces them to passive vessels rather than active handlers of content.

Calling them transporters borrows a physical-movement term that does not fit the editorial role.

Calling them mediators suggests settling disputes between parties, which is a different function.

The relay label captures how such media workers keep the message moving through successive points.