Hi @fredroo,
What do you mean by this? The plugin creates schema markup for pages and posts as Schema.org/Article or Schema.org/BlogPosting (or their respective subtypes). For MusicRecording, there is nothing in the WordPress database that would help allows us to know a page is that type. However, for custom schema markup, you can use a Generator https://www.schemaapp.com/tools/jsonld-schema-generator/MusicRecording/ to create custom markup, and copy / paste that into WordPress to override the default.
Thanks,
Mark