What PowerShell can replace hyperlinks in a PowerPoint on SharePoint Online, taking URLs from a CSV?

Hello frob009,

You can use Powerpoint COM object and open file directly from SharePoint online and then perform needed manipulations.

Something like this:

Add-type -AssemblyName office
$PowerpointFile = "<SharePoint Online URL to file"
$Powerpoint = New-Object -ComObject powerpoint.application
$ppt = $Powerpoint.presentations.open($PowerpointFile, 2, $True, $False)
$URLMap=Import-Csv .\URLMapping.csv

foreach($slide in $ppt.slides){
    foreach ($h in $slide.Hyperlinks){
        $NewURL=$URLMap | Where-Object {$_.OldURL -eq $h.Address} | Select -ExpandProperty NewURL
        if($NewURL){
            Write-Output "Old Url: $($h.Address)"
            $h.Address=$NewURL
            Write-Output "New Url: $($h.Address)"
        }
    } 
}

Sleep -Seconds 3
$ppt.Save()
Sleep -Seconds 3
$Powerpoint.Quit()

Refences: 

Hey, Scripting Guy! How Can I Customize Microsoft PowerPoint Presentations? - Scripting Blog

powershell edit powerpoint slide notes - Stack Overflow

Hope that helps.