VBA Identifiers (variable and function names) can use the Latin script and may also be able to use Japanese, Korean, Simplified Chinese, and Traditional Chinese scripts.
The extended Latin script has full coverage for many languages:
English, French, Spanish, German, Italian, Breton, Catalan, Danish, Estonian, Finnish, Icelandic, Indonesian, Irish, Lojban, Mapudungun, Norwegian, Portuguese, Scottish Gaelic, Swedish, Tagalog
Some languages are only partially covered:
Azeri, Croatian, Czech, Esperanto, Hungarian, Latvian, Lithuanian, Polish, Romanian, Serbian, Slovak, Slovenian, Turkish, Yoruba, Welsh
Some languages have little or no coverage:
Arabic, Bulgarian, Cherokee, Dzongkha, Greek, Hindi, Macedonian, Malayalam, Mongolian, Russian, Sanskrit, Thai, Tibetan, Urdu, Uyghur
The following variable declarations are all valid:
Dim Yec’hed As String 'Breton
Dim «Dóna» As String 'Catalan
Dim fræk As String 'Danish
Dim tšellomängija As String 'Estonian
Dim Törkylempijävongahdus As String 'Finnish
Dim j’examine As String 'French
Dim Paß As String 'German
Dim þjófum As String 'Icelandic
Dim hÓighe As String 'Irish
Dim sofybakni As String 'Lojban (.o’i does not work)
Dim ñizol As String 'Mapudungun
Dim Vår As String 'Norwegian
Dim «brações» As String 'Portuguese
Dim d’fhàg As String 'Scottish Gaelic
Note that in the VBA IDE, a single apostrophe within a variable name does not turn the line into a comment (as it does on Stack Overflow).
Also, languages that use two angles to indicate a quote «» are allowed to use those in variable names desipte the fact that the ""-type quotes are not.