Custom actions are not available in the Essentials solution.
If you have a Professional solution, you must purchase the Hybrid add-on to create this custom action.
If you are looking for a way to add a computer to an on-premise group you can use the following script:
In Powershell:
param ([string]$Group, [string]$Computer)
$Comp = Get-ADComputer -Identity "$Computer"
ADD-ADGroupMember -identity $Group –members $CompIn a CoreView custom action:
{
"id": "21ba9856-5928-4d09-ad02-c8f2bd08f90e",
"title": "Add Computer to Group",
"description": "Add this computer to a Group",
"lastModified": "2022-08-19T14:35:36.4460000Z",
"target": "None",
"tags": [],
"vars": [
{
"name": "Group",
"type": "string",
"isRequired": true
},
{
"name": "Computer",
"type": "string",
"isRequired": true
}
],
"params": [],
"columns": {},
"version": 4,
"statement": "param ([string]$Group, [string]$Computer)\r\n\r\n$Comp = Get-ADComputer -Identity \"$Computer\" | Select-Object DistinguishedName\nADD-ADGroupMember -identity $Group –members $Comp.DistinguishedName"
}