Many publishers require special approval for custom medley titles. And in some cases, there are specific rules prohibiting the use of an Artist name in the title of a medley or mashup. (e.g. "The Beatles Medley" is not permitted for publication without special permission.)
This is why we set up the medley/mashup feature with a specific logic to indicate the arrangement is a "medley" at the beginning of the title, then list the songs in the order you select, ensuring all metadata is included and that your arrangement will appear in customer search results just like single-song arrangements.