I am getting this stacktrace:
System.Runtime.InteropServices.COMException (0x800A13E9): Word ðú÷ì ááòéä.
at Microsoft.Office.Interop.Word.Documents.Add(
Update
Microsoft has fixed the issue with an update.
For all who have the issue with the regional format please update your Office to the Version 1902 (Build 11328.20158).
You might need to change to the monthly update channel to get it.
For Windows 10 1809 users the issue might come from the windows regional format settings.
It seems that there is an issue when you use a special regional format like "English (Switzerland)".
If you change it to "English (UK)" everything works fine.
The information about this I have found here
Hope this helps someone who still face the issue.