The Nigerian style of music known as Afrobeats has quietly entranced a large swathe of the world’s population. “Pretty much every song on pop radio [in the U.K. now] is sort of a Mr. Eazi-style, chill, afrobeats [track],” the producer Riton told Rolling Stone last year. But Nigerian singers have not yet established a foothold Stateside, despite well-received, afrobeats-dusted singles …