Good plugin, but there's another one that does much more : Music Sheet Viewer. It supports not only MusicXML, but ABC, MEI.. It allows playback on the fly with a good audio rendering, and the notes can be highlighted when played. It supports multi-pages scores, multiple SMuFL fonts, and the pages are turned automatically when played! At last it's responsive and displays on all devices.. Go to https://wordpress.org/plugins/music-sheet-viewer