Extract text from alphanumeric strings. Formula, udf or code.

Function AlphaNum(txt As String, Optional Alpha As Boolean = True) String
With CreateObject("VBScript.RegExp")
    .Pattern = IIf(Alpha, "\d+", "\D+")
    .Global = True
    AlphaNum = .replace(txt,"")
End With
End Function

Function TextOnly(rng As Range) As String

Dim intChrCnt As Integer
    For intChrCnt = 1 To Len(rng)
        If IsNumeric((Mid$(rng, intChrCnt, 1))) = False Then
            TextOnly = TextOnly & Mid$(rng, intChrCnt, 1)
        End If
    Next
    
End Function

Function AlphaNum(txt As String, Optional Alpha As Boolean = True) String

Function AlphaNum(txt As String, Optional Alpha As Boolean = True) As String

Function AlphaExtract(txt As String, Optional varDefaultVal As Variant) As String

    'Use in a cell like any Excel function, i.e. _
    =AlphaExtract(A4,"cups")
    'will extract the text from A4 or return 'cups' _
    (though this can be text or a value) if there's no text in A4.

    With CreateObject("VBScript.RegExp")
        .Pattern = ("\d+")
        .Global = True
        AlphaExtract = .Replace(txt, "")
    End With
    
    If AlphaExtract = "" Then AlphaExtract = varDefaultVal
    
End Function