ConvertTo-Mockaco.ps1

function ConvertTo-Mockaco {
    [CmdletBinding()]
    param (
        [Parameter(Mandatory=$true, Position=0, ValueFromPipeline=$true)]
        [object]
        $Har,

        # Output path to Mockaco Mocks folder
        [Parameter(Mandatory=$false)]
        [string]
        $OutputPath = (Get-Location)
    )

    Process {
        if (-not(Test-Path -Path "$OutputPath\file")) {
            New-Item -ItemType Directory -Path "$OutputPath\file" | Out-Null
        }
        foreach ($Entry in $Har.log.entries) {
            $Request = ConvertTo-Request -Entry $Entry
            $SuggestedFilename = $Request.SuggestedFilename
            $Request.Remove('SuggestedFilename')
            $Response = ConvertTo-Response -Entry $Entry -OutputPath $OutputPath
            $Metadata = @{
                request = $Request
                response = $Response
            }
            $Json = ConvertTo-Json $Metadata
            Set-Content -Path (Join-Path -Path $OutputPath -ChildPath $SuggestedFilename) -Value $Json
        }
    }
}

function ConvertTo-Request {
    param (
        [object]
        $Entry
    )

    Process {
        $Request = $Entry.request
        $Uri = [System.Uri]::new($Request.url)
        $Filename = [System.IO.Path]::GetFileName($Uri.AbsolutePath)
        $Output = @{ 
            method = $Request.method
            route = $Uri.AbsolutePath.TrimStart('/')
            SuggestedFilename = "$($Filename).json"
        }

        return $Output
    }
}

function ConvertTo-Response {
    param (
        [object]
        $Entry,

        [string]
        $OutputPath
    )

    Begin {
        $IgnoredHeaders = 'Date', 'Server', 'Accept-Ranges', 'Last-Modified', 'Content-Encoding', 'Content-Length', 'Keep-Alive', 'Connection'
    }

    Process {
        $Uri = [System.Uri]::new($Entry.request.url)
        $Filename = [System.IO.Path]::GetFileName($Uri.AbsolutePath)
        if ($Entry.response.content.mimeType -like 'text/html*') {
            $Filename += ".html"
        }
        $Output = @{
            status = 'OK'
            headers = @{}
            file = "Mocks/file/$Filename"
        }
        $ExposedHeaders = $Entry.response.headers | ?{ $IgnoredHeaders -notcontains $_.name }
        foreach ($Header in $ExposedHeaders) {
            $Output.headers[$Header.name] = $Header.value
        }
        Set-Content -Path (Join-Path -Path $OutputPath -ChildPath "file\$Filename") -Value $Entry.response.content.text

        return $Output
    }
}

Usage example:

Get-Content -Path 'C:\path\to\url_Archive `[21-01-22 09-46-54`].har' | Out-String | ConvertFrom-Json | ConvertTo-Mockaco -OutputPath 'C:\path\to\Mockaco\Mocks'