[BUG]

[glpallavi]

Describe the scenario
We are working on a SharePoint 2016 → SharePoint Online migration project and need to modernize publishing pages (including blog pages and web part pages) as part of the migration process.

Our current migration approach uses ShareGate to migrate content, but we want to ensure that pages are modernized properly using the PnP Modernization Framework.

What we tried

Installed PnP.PowerShell v3.x → Works for SPO, but cannot connect to SP2016 (404 / AADSTS errors).

Installed PnP.PowerShell v1.12.0 → Supports -TransformationOnPrem, but we still get (403) Forbidden connecting to SP2016, even with -CurrentCredentials or -Credentials.

CSOM with ClientContext.Credentials = [System.Net.CredentialCache]::DefaultNetworkCredentials works fine for SP2016.

Tried Convert-BlogPages.ps1 sample script — fails at Connect-PnPOnline -TransformationOnPrem.

Our questions

What is the recommended PowerShell module today for on-prem (SP2016) → SPO page transformation?

Should we use PnP.PowerShell (1.x) or revert to SharePointPnPPowerShellOnline 3.x + manually load the modernization DLL?

Is -TransformationOnPrem still supported / recommended in PnP.PowerShell, or is the guidance to use the legacy module?

What is the correct authentication approach for SP2016?

Should we rely on -CurrentCredentials (NTLM/Kerberos)?

Or always pass explicit credentials?

Do you have an updated reference script for hybrid page transformation that works with the currently supported modules?

Any guidance on best practice for handling publishing pages that are not in the Pages library (like default.aspx at root)?

Environment

Source: SP2016 On-Premises (NTLM Authentication, Windows Integrated Auth works in browser)

Target: SharePoint Online (Modern Team Site)

PowerShell: Windows PowerShell 5.1 (ISE + console)

Modules tested:

PnP.PowerShell 3.1.0 (PowerShell 7 required — cannot use on Windows PS5.1)

PnP.PowerShell 1.12.0 (fails connecting to SP2016)

SharePointPnPPowerShellOnline 3.29.2101.0 (not yet tested with DLL approach)

Goal

We are looking for a clear recommendation from the PnP team:

The supported combination of modules / DLLs to use in 2025 for SP2016 → SPO modernization.

A sample end-to-end process (connect source + target, transform pages, output logs).