For your application you don't actually need two arrays at all.
 Code:
$IPMAC_8TH="192.168.2.85 0021851165F4",
           "192.168.2.92 002144CB2F43",
           "192.168.2.168 002168D92EA8"
              
For Each $IPMAC in $IPMAC_8th
	Shell "cmd.exe /c wol.exe "+$IPMAC
Next