AssetDatabase.MoveAsset
static function MoveAsset(oldPath: string, newPath: string): string;
static string MoveAsset(string oldPath, string newPath);
static def MoveAsset(oldPath as string, newPath as string) as string
Parameters

oldPath The path where the asset currently resides.
newPath The path which the asset should be moved to.
Returns
string An empty string if the asset has been successfully moved, otherwise an error message.
Description

Move an asset file from one folder to another.

All paths are relative to the project folder, for example: "AssetsMyTextureshello.png".