Change Office 365 Portal Language Settings
I will try to show you a workaround that will help you to Change Office 365 Portal Language Settings for SharePoint based Applications.
It is very useful especially if you gone mad as me when you can’t see the language settings under account settings : )
The problem is some Office 365 Online applications like OneNote and OneDrive use SharePoint and they might appear in non English language, in my case Turkish, whilst our O365 organisation lang is configured to use English.
OneDrive – Non-English
OneNote Online – Non-English
Here is the fix, change the URL in site address bar to …./_layouts/15/muisetng.aspx and press Enter
You will see your personal SharePoint site language settings, nice huh?, change it as you wish and click OK.
It will change your language and redirect you to “your” site settings, /settings.aspx which is easier to remember, don’t forget it you might need that again.
Now checking OneNote, yes now it uses English as the language. Hope it helps to you too.