Recently I was working on a paper which talks about a certain musician's incorporation of multiple styles and influences.....
Is there a more concise way to say "incorporate multiple influences"?
Eclectic has the connotations of containing/being influenced by a variety of genres.
Often the word "fusion" is used to describe combined influences in various endeavors.
It was used alone to denote a combination of jazz and rock music which became popular in the 1970's-'80's - but, would not be out of place describing the melding of other styles of music.
The word synthesis is a perfect match here:
Synthesis: The combination of components or elements to form a connected whole. ‘the synthesis of intellect and emotion in his work’
Here’s a paragraph of some music related text (source) that demonstrates it well:
The blues became marked as a distinctive musical genre around the turn of the 20th century, developing throughout the Southeast as a synthesis of the African American music traditions which preceded it, including work songs, field hollers, dance tunes, minstrel songs, and spirituals.