How to make the avatar become transparent In Unity?

I have a requirement in my project, i need to make the avatar loaded by scirpt becoming transparent in unity, does readyplayerme have this function?

It’s not a feature of Ready Player Me, you have to do it yourself.

You can remove the material from the Skinned Mesh Renderer Component of the avatar gameobject. You can do it manually in the editor (see screenshot) or via code at runtime (check SkinnedMeshRenderer API Unity). This will make it invisible, if you want to make it transparent but still visible, you will need to create your custom Shader for that.