How to influence OneDrive's Known Folder Move and target specific cloud folders. Part of a blog series on https://allthingscloud.blog.

Set-OneDriveDocumentsFolder.ps1

<#
    .SYNOPSIS    
    Mark the OneDrive folder '\Documen-ta-daa' as the target for the 'Documents'-folder during KFM.
    
    .DESCRIPTION
    This script is part of the blog series on OneDrive's Known Folder Move and how to influence it. 
    Please visit https://allthingscloud.blog/onedrive-and-its-unknown-folder-move-kfm-part-1/ and https://allthingscloud.blog/onedrive-and-its-unknown-folder-move-kfm-part-2/ for more information. 
    
    .NOTES
    Author: Niels Scheffers <niels.scheffers@etesian.nl>    
    Last modified: 2022-03-14  
#>
$siteUrl = 'https://notreally-my.SharePoint.com/personal/n_scheffers_alsonotreally_nl';
$documentsFolderName = 'Documen-ta-daa';
Import-Module -Name PnP.PowerShell;
Connect-PnPOnline -Url $siteUrl -Interactive;
$siteCtx = Get-PnPContext;
$documentsList = Get-PnPList -Identity 'Documents';
if ($siteCtx -and $documentsList) {
    $documentsListUrl = $documentsList.RootFolder.ServerRelativeUrl;
    $documentsFolderUrl = "$($documentsListUrl)/$($documentsFolderName)";
    $documentsFolder = Get-PnPFolder -Url $documentsFolderUrl;
    $siteCtx.Load($documentsFolder.ListItemAllFields);
    $siteCtx.ExecuteQuery();
    if ($documentsFolder) {
        $documentsFolderGuid = $documentsFolder.ListItemAllFields.FieldValues['UniqueId'];
        if ($documentsFolderGuid) {
            $documentsList.RootFolder.Properties['vti_DocumentsFolderGuid'] `
                = $documentsFolderGuid.ToString();
            $documentsList.RootFolder.Update();
            $siteCtx.ExecuteQuery();
        }
    }
}

Set-OneDriveDocumentsFolder_Additional.ps1

<#
   .SYNOPSIS    
   Other KFM properties in OneDrive that can be used as described in the other script in this Gist.    
   
   .DESCRIPTION
    This script is part of the blog series on OneDrive's Known Folder Move and how to influence it. 
    Please visit https://allthingscloud.blog/onedrive-and-its-unknown-folder-move-kfm-part-1/ and https://allthingscloud.blog/onedrive-and-its-unknown-folder-move-kfm-part-2/ for more information. 

    .NOTES
    Author: Niels Scheffers <niels.scheffers@etesian.nl>    
    Last modified: 2022-03-14  
#>
$documentsList.RootFolder.Properties['vti_DesktopFolderGuid'];
$documentsList.RootFolder.Properties['vti_DocumentsFolderGuid'];
$documentsList.RootFolder.Properties['vti_CameraRollFolderGuid'];
$documentsList.RootFolder.Properties['vti_ScreenShotsFolderGuid'];
$documentsList.RootFolder.Properties['vti_PhotosFolderGuid'];