Karabiner: Left Command -> ENG, Left Option -> RU

rule.json

{
    "description": "L_CMD -> ENG, L_OPT -> RU",
    "manipulators": [
        {
            "type": "basic",
            "from": {
                "key_code": "left_command",
                "modifiers": {
                    "optional": [
                        "any"
                    ]
                }
            },
            "to": [
                {
                    "key_code": "left_command",
                    "lazy": true
                }
            ],
            "to_if_alone": [
                {
                    "select_input_source": {
                        "language": "en"
                    }
                }
            ],
            "to_if_held_down": [
                {
                    "key_code": "left_command"
                }
            ],
            "parameters": {
                "basic.to_if_alone_timeout_milliseconds": 500,
                "basic.to_if_held_down_threshold_milliseconds": 500
            }
        },
        {
            "type": "basic",
            "from": {
                "key_code": "left_option",
                "modifiers": {
                    "optional": [
                        "any"
                    ]
                }
            },
            "to": [
                {
                    "key_code": "left_option",
                    "lazy": true
                }
            ],
            "to_if_alone": [
                {
                    "select_input_source": {
                        "language": "ru"
                    }
                }
            ],
            "to_if_held_down": [
                {
                    "key_code": "left_option"
                }
            ],
            "parameters": {
                "basic.to_if_alone_timeout_milliseconds": 500,
                "basic.to_if_held_down_threshold_milliseconds": 500
            }
        }
    ]
}