Assert Tenant Templates from source tenant are also in the second tenant and contain the same base templates.

Test-TenantTemplates.ps1

$aName = "Metro"
$aName = "Crafted"

$fromName = "/$aName/"
$toName = "/$($aName)VC/"

$tenantFrom = gci "master:\templates\Project$fromName" | ? { $_.TemplateName -eq "Template" }
$tenantFromIDs = $tenantFrom.ID;
$tenantTo   = gci "master:\templates\Project$toName" | ? { $_.TemplateName -eq "Template" }
$tenantToIDs = $tenantTo.ID;

$templateGroups = (($tenantFrom + $tenantTo) | Group-Object -Property "Name")
$templateGroups | % {
    
    $fromTemplate = $_.Group | ? { $_.Paths.Path.Contains($fromName) } 
    $toTemplate   = $_.Group | ? { $_.Paths.Path.Contains($toName) }

    if($toTemplate -eq $null)
    {
        Write-Host "'$($fromTemplate.Name)' template is missing in $toName" -f Red
    } elseif($fromTemplate -eq $null){
        Write-Host "'$($toTemplate.Name)' template is missing in $fromName" -f Yellow
    } else {
        $fromTemplateBase =  $fromTemplate._.'__Base template'.GetItems();
        $fromTemplateBaseIDs = @() + $fromTemplateBase.ID;
        $toTemplateBase   =  $toTemplate._.'__Base template'.GetItems();
        $toTemplateBaseIDs = @() + $toTemplateBase.ID;
        
        $fromTemplateBaseIDs | ? { !$toTemplateBaseIDs.Contains($_) -and !$tenantFromIDs.Contains($_)} | 
        %{
            $missingTemplate = gi master: -ID $_
            if($missingTemplate.Paths.Path.Contains("/Project/")){
                Write-Host "$($fromTemplate.Paths.Path) inherit from $($missingTemplate.Paths.Path) - most likely wrongly" -f Red
            } elseif ($missingTemplate.Paths.Path.Contains("/sitecore/templates/System/")){
                Write-Host "$($fromTemplate.Paths.Path) inherit from $($missingTemplate.Paths.Path) - unnecessarily?" -f Red
            } else {
                Write-Host "$($toTemplate.Paths.Path) Should inherit from $($missingTemplate.Paths.Path) - implementing the change"  -f Green
                Add-BaseTemplate -Item $toTemplate -TemplateItem $missingTemplate -WhatIf
            }
        }
    }
}