dual WAN on dual NIC - need help with opnsense

[nhk_]

hi all,

maybe this is an easy thing to solve but for the life of me I can't figure it out.

I have two ISPs in Australia, one is DHCP WAN and one is PPOE WAN. DHCP WAN is 100mbit, PPOE WAN is 50mbit.

I want to use the PPOE WAN on one specific computer on my network and only one. Everything else can use the DHCP WAN 100mbit line.

I've read a billion documents on vlans and tagged and untagged ports and don't understand at all how this applies to my situation, I seem to be unable to select the WAN connection in opnsense for a specific ip. So i'm quite lost.

any ideas or pointers?

I have:

WAN1 >>> DUAL NIC SLOT 1
WAN2 >>> DUAL NIC SLOT 2
LAN >>> management port in esxi and LAN for all guests

all ethernet cables connected to a managed switch. It seems incredibly difficult when I mean I could just pick up a spare router, connect WAN2 to it, connect an ethernet cable from the spare router to the pc i want to use that connection and be done. but surely theres a way with opnsense and my dual nic + onboard nic?