Try this for starters. It should be pretty easy to follow.
It goes down List1 and tries to find a match with values in List2, highlighting accordingly.
Values in List2 that are NOT in List1 remain unchanged.
LR_List1 = ActiveSheet.Range("A" & Rows.Count).End(xlUp).Row
LR_List2 = ActiveSheet.Range("B" & Rows.Count).End(xlUp).Row
For n = 2 To LR_List1
myvalue1 = Cells(n, 1).Value
Match = False
For m = 2 To LR_List2
myvalue2 = Cells(m, 2).Value
If myvalue1 = myvalue2 Then
Cells(n, 1).Interior.ColorIndex = 4 'Green
Cells(m, 2).Interior.ColorIndex = 4 'Green
Match = True
If Match = False Then
Cells(n, 1).Interior.ColorIndex = 3 ' Red