So I have added multiple nics both physical and virtual to my esxi host and to the pfsense vm.
So depending on what vswitches you connect your physical too and then how you assign them in pfsense doesn't really matter. You can assign whatever nic you want to the lan, or opt, etc.
So when I first brought up pfsense virtual it had em0 and em1 – I then added 2 more virtual nics in esxi. em2, em3 -- see how assigned in screenshot attached.
The you can assign them to whatever vswitches you want in esxi, does not matter if physical nic on this switch or not - for example my dmz vswitch does not connect to the physical world. But pfsense sees it as interface on my lan, etc.
When you add new virtual nics to the vm, reboot pfsense and it will see them - then you can assign them however you want in pfsense.
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