Okay, so starting from LastCell thing, here you got some information about it: http://www.cpearson.com/excel/LastCell.aspx
It was not so easy, because you have merged cells so I had to make a little workaround. First step I am counting number of cells in Worksheets List
from your example. Later I am using autofill to fill as many cells as needed - columns G:I and copying formats in the same Cells in column J. Last step is to copy values from column J.
It's kinda strange but it is all thanks to merged cells ;)
Hope it works.
Sub counting()
Dim WS As Worksheet
Dim LastCell As Range
Dim LastCellRowNumber As Long
Set WS = Worksheets("List") 'your worksheet name
With WS
Set LastCell = .Cells(.Rows.Count, "A").End(xlUp)
LastCellRowNumber = LastCell.Row
End With
Worksheets("Barcodes").Range(Cells(2, 7), Cells(3, 9)).AutoFill _
Destination:=Range(Cells(5, 7), Cells(6 + (LastCellRowNumber * 2) - 4, 9)), Type:=xlFillDefault 'filling columns from G to I
Worksheets("Barcodes").Range(Cells(2, 10), Cells(3, 10)).AutoFill _
Destination:=Range(Cells(5, 10), Cells(6 + (LastCellRowNumber * 2) - 4, 10)), Type:=xlFillFormats ' filling with format J column
j = 4
k = 5
For i = 6 To LastCellRowNumber 'filling values in column J
Cells(j, 10).Value = "=List!A" & i
Cells(k, 10).Value = "=List!B" & i
j = j + 2
k = k + 2
Next
End Sub
Editted code version 2:
Sub counting()
Dim WS As Worksheet
Dim LastCell As Range
Dim LastCellRowNumber As Long
Set WS = Worksheets("List") 'your worksheet name
With WS
Set LastCell = .Cells(.Rows.Count, "A").End(xlUp)
LastCellRowNumber = LastCell.Row
End With
Worksheets("Barcodes").Range(Cells(5, 7), Cells(6, 7)).AutoFill _
Destination:=Range(Cells(5, 7), Cells(6 + (LastCellRowNumber * 2) - 4, 7)), Type:=xlFillDefault 'filling column G
Worksheets("Barcodes").Range(Cells(5, 8), Cells(6, 9)).AutoFill _
Destination:=Range(Cells(5, 8), Cells(6 + (LastCellRowNumber * 2) - 4, 9)), Type:=xlFillFormats 'filling with columns H:J
j = 7
k = 8
For i = 3 To LastCellRowNumber 'copying values in columns I, J
Cells(j, 9).Value = "=List!A" & i
Cells(j, 8).Value = Cells(j - 2, 8).Value
Cells(k, 9).Value = "=List!B" & i
Cells(k, 8).Value = Cells(k - 2, 8).Value
j = j + 2
k = k + 2
Next
End Sub
Edition v3:
Sub auto_copy()
Dim WSL As Worksheet, WSB As Worksheet
Dim first_col As Long, second_col As Long
Dim first_r As Byte, first_c As Byte
Dim second_r As Byte, second_c As Byte
Dim LastCellRowNumber As Long, comeback As String
Dim LastCell As Range, ActiveWS As String
Application.ScreenUpdating = False
ActiveWS = ActiveSheet.Name
Set WSB = Worksheets("Barcodes") 'your worksheet name
Set WSL = Worksheets("List") 'your worksheet name
With WSL
Set LastCell = .Cells(.Rows.Count, "A").End(xlUp)
LastCellRowNumber = LastCell.Row - 3
End With
first_col = Round(LastCellRowNumber / 2)
second_col = LastCellRowNumber - first_col
first_r = 5 'position of "first column" row
first_c = 7 'position of "first column" column
second_c = 11 'position of "first column" column
WSB.Activate
comeback = ActiveCell.Address
For i = 1 To LastCellRowNumber
If Application.IsOdd(i) = True Then
WSB.Range(Cells(first_r, first_c), Cells(first_r + 1, first_c)).Copy
WSB.Range(Cells(first_r + 2, first_c), Cells(first_r + 1 + 2, first_c)).PasteSpecial
WSB.Range(Cells(first_r, first_c + 1), Cells(first_r + 1, first_c + 2)).Copy
WSB.Range(Cells(first_r + 2, first_c + 1), Cells(first_r + 1 + 2, first_c + 2)).PasteSpecial
Else
WSB.Range(Cells(first_r, second_c), Cells(first_r + 1, second_c)).Copy
WSB.Range(Cells(first_r + 2, second_c), Cells(first_r + 1 + 2, second_c)).PasteSpecial
WSB.Range(Cells(first_r, second_c + 1), Cells(first_r + 1, second_c + 2)).Copy
WSB.Range(Cells(first_r + 2, second_c + 1), Cells(first_r + 1 + 2, second_c + 2)).PasteSpecial
first_r = first_r + 2
End If
Next
Range(comeback).Activate
Worksheets(ActiveWS).Activate
Application.CutCopyMode = False
Application.ScreenUpdating = True
End Sub