Send mail with "Send As" or change sender

Question

I'm making a script to automate Outlook 2016. I have one account with two different inboxes from clients.

At the end of the script, I need to send an email from the name of the inbox the script is run from. I'm authorized to send email in the name of both inboxes, but I can't get the script to do it. I post my actual code:

The code:

Function Send-Email {
    param ([String]$desde,[String]$subject,[String]$buzon,[String]$inc)


$mail = $Outlook.CreateItem(0)
$firma ="
Textplan
"

$mail.subject = "Closed Ticket "+$subject
[String]$cuerpo =@"
Dear colleague,

bla bla bla

Thank you.
"@

$mail.sender = $buzon
$mail.body = $cuerpo+" "+$firma 
$mail.To = $desde
$mail.Send()
Start-Sleep 3

}

$Outlook = New-Object -ComObject Outlook.Application
$desde = client2@mail.com
$buzon = inbox1@mail.com
$inc = 000000001
$subject = "Automat request"
Send-Email -desde $desde -subject $asunto -buzon $Buzon1 -inc $inc

Answer 1

I finally used this lines and work well:

$mail.SentOnBehalfOfName = "inbox1d@mail.com"
$mail.SendUsingAccount = $Outlook.Session.Accounts | where {$_.DisplayName -eq $FromMail}

Function Send-Email {
    param (
        [String]$desde,
        [String]$subject,
        [String]$buzon,
        [String]$inc
    )

    $firma = 'Textplan'
    $cuerpo = "Dear colleague,`r`nbla bla bla`r`nThank you."

    $Outlook = New-Object -ComObject Outlook.Application
    $mail = $Outlook.CreateItem(0)
    $mail.subject = 'Closed Ticket ' + $subject
    $mail.sender = $buzon
    $mail.body = "$cuerpo $firma"
    $mail.SentOnBehalfOfName = "inbox1d@mail.com"
    $mail.SendUsingAccount = $Outlook.Session.Accounts | where {$_.DisplayName -eq $FromMail}
    $mail.Send()
    Start-Sleep 3
}

$desde = 'client2@mail.com'
$subject = 'Automat request'
$buzon = 'inbox1@mail.com'
$inc = '000000001'

Send-Email -desde $desde -subject $subject -buzon $buzon -inc $inc