Swap y and z with Karabiner only if input source is english

swap_y_and_z.json

{
  "Title": "Swap 'y' and 'z'",
  "rules": [
    {
      "description": "Swap 'y' and 'z'",
      "manipulators": [
        {
          "type": "basic",
          "from": {
            "key_code": "y"
          },
          "to": [
            {
              "key_code": "z"
            }
          ],
          "conditions": [
            {
              "input_sources": [
                {
                  "language": "en"
                }
              ],
              "type": "input_source_if"
            }
          ]
        },
        {
          "type": "basic",
          "from": {
            "key_code": "z"
          },
          "to": [
            {
              "key_code": "y"
            }
          ],
          "conditions": [
            {
              "input_sources": [
                {
                  "language": "en"
                }
              ],
              "type": "input_source_if"
            }
          ]
        }
      ]
    }
  ]
}