that it should not be too difficult to adapt the action(s) that are already known to you.
And if you have difficulties, the describe what you have done, what you expected and what the result actdually was.
You could try an action of the type "Format value" for ARTIST
Format string: %artist%, $regexp($regexp(%title%,'.*feat\. (.*)\)',$1),'(.*), (.*)',$1 & $2)