How to reach _redirect placed in a sub folder?

Support
12

Not sure why you are using xcopy. cp is standard copy command. I assume you have a directory structure something like this with multiple languages directories (and files) inside the root (project/publish) directory

.
├── en
│   └── index.html
├── es
│   └── index.html
└── fr
    └── index.html

So rather than having three _redirects files (one in each directory) you would have one in your root (project/publish) directory from the outset, negating the need to us cp (or xcopy).

.
├── _redirects
├── en
│   └── index.html
├── es
│   └── index.html
└── fr
    └── index.html