This music is very cool, but it also includes some cuteness.
This music is very cool, but it also has some cute aspects.
「この音楽はとてもかっこいいが、どこか可愛さも含む」は英語で以下の文になれます:
1)This music is very cool, but it also includes some cuteness.
2)This music is very cool, but it also has some cute aspects.
例2の方がもっとナチュラルだと思いますが、どちでもいいです。
この音楽 --> this music
とてもかっこいい --> very cool
どこか可愛さ --> cuteness/cute aspects/cute parts
含む --> includes/has