The kanji 自由 is unisex and is much more commonly used among females and Miyu is a much more modern name for males and isn't usually considered masculine. Some examples of names that are like Miyu are, Hiyori, Mana, Kanna, Chika and Hana. Also, 自由 is mostly read as Jiyuu (a male and female name), which is the Japanese word and kanji for freedom.