Powershell Pipes and how to remove them for Pester testing

Question

$VSwitch = Get-VMHost $HostName | get-virtualswitch -name vswitch0 -Standard

and

$VSwitch = Get-VMHost $HostName
$VSwitch = get-virtualswitch -name vswitch0 -Standard $VSwitch

Are these two functions going to be giving the same output ?

I am using Pester tests but one of them gives me an error while the other does not. I am assuming something is wrong with how I am mocking them

        $vmhost = New-MockObject -T 'VMware.VimAutomation.ViCore.Impl.V1.Inventory.VMHostImpl' -Properties @{
            Name = "esx-1.bluedog.microsoft.com"
            Datacenter = "Datacenter"
        }
        $switch_params = @{ 
            Name = "Vswitch0"
            Mtu = 5000
        }
        $switch1 = New-MockObject -T 'VMware.VimAutomation.ViCore.Impl.V1.Host.Networking.VirtualSwitchImpl' -Properties $switch_params
        
        Mock Get-VMHost { return $vmhost } -ModuleName $module
        Mock get-virtualswitch { return $switch1 } -ModuleName $module

I am using Pester tests but one of them gives me an error while the other does not. I am assuming something is wrong with how I am mocking them, I was assuming to get same output is both of them and to be able to print VSwitch0 somehow.