XL 2019 Formule pour isoler des nombres

Function Sépare(N, i)
Dim T, Place%, j%
T = Split(N, ","): Place = 1
For j = 0 To UBound(T)
    If IsNumeric(T(j)) And Place = i Then
        Sépare = T(j): Exit Function
    ElseIf IsNumeric(T(j)) Then
        Place = Place + 1
    End If
Next j
If Sépare = 0 Then Sépare = ""
End Function

=Sépare(Chaine;Position)

Sub Extraire()
Dim P As Range
Application.ScreenUpdating = False
With ActiveSheet.UsedRange.Columns(1).Offset(1)
    Set P = .Offset(, 1).Resize(, Columns.Count - .Column)
    P.ClearContents
    .TextToColumns .Offset(, 1), xlDelimited, Comma:=True 'commande Convertir
    On Error Resume Next 'si aucune SpecialCell
    P.SpecialCells(xlCellTypeConstants, 2).ClearContents
    P.SpecialCells(xlCellTypeBlanks).Delete xlToLeft
End With
End Sub

Function IsolerNombres(texte)
Dim regex As Object, Matches As Object, Match As Object, res(), i
'On Error Resume Next
Set regex = CreateObject("VBScript.RegExp")
regex.Pattern = "\d+": regex.Global = True   ' Motif \d+ -> un ou plusieurs chiffres
Set Matches = regex.Execute(texte)
ReDim res(1 To 1, 1 To Matches.Count)
i = 1
For Each Match In Matches
   res(1, i) = Match.Value
   i = i + 1
Next Match
IsolerNombres = res
Set regex = Nothing
End Function

Sub TstIsolerNombres()
 IsolerNombres "1, 8, 14, 17"
End Sub

=REGEX.EXTRAIRE(A1;"\d+";1)

=SIERREUR(INDEX(TRANSPOSE(SI(FILTRE.XML("<t><s>"&SUBSTITUE($A1;",";"</s><s>")&"</s></t>";"//s")>="A";"";FILTRE.XML("<t><s>"&SUBSTITUE($A1;",";"</s><s>")&"</s></t>";"//s")));COLONNE(A1));"")