Regex search function

I’m trying to figure out how to write a regex function that allows a script to do this:

Write the name of the artist in a new variable only if it is [mixer] or [something else mixer] (for example [guitar mixer]).
It does not have to write anything if it is [additional mixer] or [something else additional mixer] or [remixer] or [assistant mixer] etc…

The reference template is: artist name:[role]