You can use a function node to define the message yourself, or simply use a change node. Just change the payload from the Input_boolean to be the desired JSON Object. Before that you probably want to filter with a switch node for on & off state of the boolean.
Like this:
[
{
"id": "80b13b00.3bd6c8",
"type": "server-state-changed",
"z": "6b8efe0d.bc75e",
"name": "",
"server": "2fba4297.e4145e",
"version": 1,
"exposeToHomeAssistant": false,
"haConfig": [
{
"property": "name",
"value": ""
},
{
"property": "icon",
"value": ""
}
],
"entityidfilter": "input_boolean.abkuhlen",
"entityidfiltertype": "exact",
"outputinitially": false,
"state_type": "str",
"haltifstate": "",
"halt_if_type": "str",
"halt_if_compare": "is",
"outputs": 1,
"output_only_on_state_change": true,
"x": 880,
"y": 540,
"wires": [
[
"afabc574.ef25f8"
]
]
},
{
"id": "afabc574.ef25f8",
"type": "switch",
"z": "6b8efe0d.bc75e",
"name": "",
"property": "payload",
"propertyType": "msg",
"rules": [
{
"t": "eq",
"v": "on",
"vt": "str"
},
{
"t": "eq",
"v": "off",
"vt": "str"
}
],
"checkall": "true",
"repair": false,
"outputs": 2,
"x": 1110,
"y": 540,
"wires": [
[
"261d3bf9.b9dc54"
],
[
"cb1a415d.7371e"
]
]
},
{
"id": "261d3bf9.b9dc54",
"type": "change",
"z": "6b8efe0d.bc75e",
"name": "",
"rules": [
{
"t": "set",
"p": "payload",
"pt": "msg",
"to": "{\"NewEnable\":\"1\"}",
"tot": "json"
}
],
"action": "",
"property": "",
"from": "",
"to": "",
"reg": false,
"x": 1290,
"y": 500,
"wires": [
[]
]
},
{
"id": "cb1a415d.7371e",
"type": "change",
"z": "6b8efe0d.bc75e",
"name": "",
"rules": [
{
"t": "set",
"p": "payload",
"pt": "msg",
"to": "{\"NewEnable\":\"0\"}",
"tot": "json"
}
],
"action": "",
"property": "",
"from": "",
"to": "",
"reg": false,
"x": 1290,
"y": 580,
"wires": [
[]
]
},
{
"id": "2fba4297.e4145e",
"type": "server",
"z": "",
"name": "Home Assistant",
"legacy": false,
"addon": true,
"rejectUnauthorizedCerts": true,
"ha_boolean": "y|yes|true|on|home|open",
"connectionDelay": true
}
]