You can do it to your existing scrobbles through LastFm Pro, editing them to the specific tag that you want. Now to your future scrobbles, if you use iOS only Apple Music can do it, you can edit the tags and once you listen the songs, it already scrobble to the tag that you put it on (on Android you can do it too). On Android you still can do it even if you don't use Apple Music, let me know if you want to learn it.