Windows 10 Enterprise Activation

Hello everyone,

I am starting this post to get clarifications on the Windows 10 activation matter, following OS installation.

Scenario: coming soon Microsoft 365 E3/E5 Enterprise licenses; Access to MAKs; full-cloud managed machines, AAD-joined via Endpoint Manager and Autopilot.

To my understanding, Windows 10 activation can be performed in these two "regular" ways, both of them requiring upgrade from Win 10 Pro to Enterprise:

1) Via Windows 10 Enterprise E3/E5 licenses, by assigning them to Active users;

2) Via Endpoint Manager, by setting up Edition Upgrade profile's template, but it requires a MAK for Windows 10 Enterprise

My questions:

• Are the two linked somehow? I mean, is the activation through 1) still linked to a MAK (but we don't notice it)?
• What is the most suitable one?
• If I have access to MAKs (including Enterprise) is it a waste of money buying Windows 10 Enterprise E3 or E5 licenses (sorry for the silly question :-)?
• going through Win Pro to Enterprise upgrade is it still a requirement? Isn't there a way to automate Enterprise activation following its fresh installation, apart from deploying ad-hoc PowerShell script?

Thank you in advance!

Gianluca