Project Templates seem to be stored in AppData\Local\Microsoft\VisualStudio\<VS_Install_ID>\Extensions\<Extension_ID>\<TemplateType>\CSharp\1033 (1033 being the English locale ID). It appears if the language in Tools > Options > Environment > International Settings isn't set to English, the templates won't show up.
Project Templates seem to be stored in
AppData\Local\Microsoft\VisualStudio\<VS_Install_ID>\Extensions\<Extension_ID>\<TemplateType>\CSharp\1033(1033 being the English locale ID). It appears if the language inTools > Options > Environment > International Settingsisn't set to English, the templates won't show up.