N editions are not really a feature but MSFT has to make them because of European LAW. Afaik, only EU countries, Korean and US ISO's contain the N editions.
I've updated my original reply to you asking if your problem might be because you're tying to run the script using an old version of Powershell? Also, is your image US English? see Post #901 - seems only US English language images are supported. And finally, I've updated my post and replaced my modified LTSC 2019 script with a link to the new unmodified official version. @GodHand has uploaded a new version 3.1.1.6 of Optimize-Offline.ps1 to GitHub. This new version natively processes LTSC 2019. You should try using his unmodified script and if you continue to have problems, we'll try and help, but you can also request support from @GodHand.
If I add anything to LTSC specifically it will be such things as slipstreaming Edge and Appx Packages (which I already have coded out and working within the script). I decided to toss an optimized + slipstreamed version of LTSC 2019 on one of my ThinkPads (they can get very picky with modified OS installations) and everything is working flawlessly, even down to the proprietary software Lenovo offers exclusively.
Does anyone have issue rebooting? Sometimes my notebook get stuck and I need to hold power button to shut it down...
Someone should make a fork of this script that will support all languages, a lot of users here are european and don't use en-US .iso images, including me.