Female name.
Generally, there are quite a lot of girls with names with the word jade, and jade also represents flawless beauty.
But Zhang Liangyu can also be used as a boy’s name, because Liang Yu’s homophone is Liangyu, which also represents the hope that the children will grow up. It depends on the meaning of the family when choosing the name. Both boys and girls can use it as long as they think it's a good name.