How to filter custom directory roles from Powershell Or CLI

I have few custom directory roles with specific permissions. I attempted to do it from graph but no use, throwing errors.

Is there any other possible way to get that list from Powershell Or CLI.

Get-AzRoleDefinition

Getting all roles, how to add custom role filter for this command?

I tried to reproduce the same in my environment to get the custom roles using PowerShell

Here is the script to get Azure custom roles with Filter.

#import and Install Az Module
Import-Module Az.Accounts
Install-Module -Name Az -Scope CurrentUser -Repository PSGallery -Force
#connect-Azure Account
Connect-AzAccount
#Get All Azure AzRoleDefinition
Get-AzRoleDefinition
Get-AzRoleDefinition -Name Reader
#Get Custom Roles
Get-AzRoleDefinition -Custom |? {$_.IsCustom -eq $true}| FT Name,IsCustom,Id




 

Output with Filter command.

Reference : Azure custom role using Azure PowerShell