project-manager/plugins/plesk/etc/config.json

{
    "plesk": {
        "plesk_host": null,
        "plesk_user": null,
        "plesk_private_key": null,
        "plesk_private_key_passphrase": null,
        "plesk_public_key": null,
        "plesk_db_type": null,
        "plesk_binary": "plesk"
    }
}