Sub u_5()
    '5
    Application.ScreenUpdating = False
    'левые
    For Each b In Range("a1:a1400")
        crow = b.Row
        cleft = "*" & Left(b, InStrRev(b, ",") - 1) & ",*"
        g = Application.CountIf(Range("a1:a1400"), cleft)
        If g > 1 Then
            e = 1
            For h = 1 To g
        
                d = Application.Match(cleft, Range("a" & e & ":a1400"), 0)
                e = e + d
                If e - 1 <> crow Then
                    f = Cells(crow, Columns.Count).End(xlToLeft).Column + 1
                    Cells(crow, f) = Range("a" & e - 1).Value
                End If
            
            Next
        End If
    Next
    'правые
    For Each b In Range("a1:a1400")
        crow = b.Row
        cright = "*," & Mid(b, InStr(b, ",") + 1, 17) & "*"
        g = Application.CountIf(Range("a1:a1400"), cright)
        If g > 1 Then
            e = 1
            For h = 1 To g
                d = Application.Match(cright, Range("a" & e & ":a1400"), 0)
                e = e + d
                If e - 1 <> crow Then
                    f = Cells(crow, Columns.Count).End(xlToLeft).Column + 1
                    Cells(crow, f) = Range("a" & e - 1).Value
                End If
            Next
        End If
    Next
    Application.ScreenUpdating = True
End Sub
Sub u_4()
    '4
    Application.ScreenUpdating = False
    'левые
    For Each b In Range("a1:a1400")
        crow = b.Row
        cleft = "*" & Left(Left(b, InStrRev(b, ",") - 1), InStrRev(b, ",") - 1) & ",*"
        g = Application.CountIf(Range("a1:a1400"), cleft)
        If g > 1 Then
            e = 1
            For h = 1 To g
        
                d = Application.Match(cleft, Range("a" & e & ":a1400"), 0)
                e = e + d
                If e - 1 <> crow Then
                    f = Cells(crow, Columns.Count).End(xlToLeft).Column + 1
                    Cells(crow, f) = Range("a" & e - 1).Value
                End If
            
            Next
        End If
    Next
    'правые
    For Each b In Range("a1:a1400")
        crow = b.Row
        cright = "*," & Mid(Mid(b, InStr(b, ",") + 1, 17), InStr(b, ",") + 1, 17) & "*"
        g = Application.CountIf(Range("a1:a1400"), cright)
        If g > 1 Then
            e = 1
            For h = 1 To g
                d = Application.Match(cright, Range("a" & e & ":a1400"), 0)
                e = e + d
                If e - 1 <> crow Then
                    f = Cells(crow, Columns.Count).End(xlToLeft).Column + 1
                    Cells(crow, f) = Range("a" & e - 1).Value
                End If
            Next
        End If
    Next
    Application.ScreenUpdating = True
End Sub

let
Источник = Table.FuzzyNestedJoin(Таблица1, {"Столбец1"}, Таблица1, {"Столбец1"}, "Таблица1", JoinKind.Inner, [IgnoreCase=true, IgnoreSpace=true, Threshold=0.75]),
#"Развернутый элемент Таблица1" = Table.ExpandTableColumn(Источник, "Таблица1", {"Столбец1"}, {"Таблица1.Столбец1"})
in
#"Развернутый элемент Таблица1"