As I reported in #8815, prettier doesn't support UTF-16LE config files. The documentation still gives instructions that will result in a UTF-16LE file and give users very confusing instructions. I ran into this again, 2 years later while setting up a new project. Powershell is a very common terminal for Windows developers to work in and I'm sure this will result in confusion by others as well.
Environments:

• Prettier Version: 2.8.0
• Running Prettier via: npx prettier --write .
• Runtime: Powershell inside of vscode
• Operating System: Windows 10
• Prettier plugins (if any): N/A

Steps to reproduce:

Follow the installation instructions in a powershell prompt:

• npm install --save-dev --save-exact prettier
• echo {}> .prettierrc.json <--- the problematic command
• npx prettier --write .

Expected behavior:
Prettier recognizes an empty json config file
Actual behavior:
You get the hideous error message:

[error] Invalid configuration file `.prettierrc.json`: JSON Error in <file path>\.prettierrc.json: 
[error]
[error] > 1 | ��
[error]     | ^
[error]   2 |
[error]   3 |
[error]
[error] Unexpected token "�" (0xFFFD) in JSON at position 0 while parsing "��\r\u0000\n\u0000"
[error]
[error] > 1 | ��
[error]     | ^
[error]   2 |
[error]   3 |
[error]

Saving the file with UTF-8 encoding produces the expected result of running with an empty config file.