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not working for me, 2.5.0, maybe they are valid for 2.4.5 but I can't test on it.
if it's only for 2.4.5 it will become old as soon as 2.5.0 is released

sysctl: unknown oid 'hw.vmx.txnqueue'

I think the new oid, following your example, are

dev.vmx.0.iflib.override_ntxds=2048,2048
dev.vmx.0.iflib.override_nrxds=2048,2048
dev.vmx.0.iflib.override_ntxqs=8
dev.vmx.0.iflib.override_nrxqs=8

[2.5.0-DEVELOPMENT][root@pfSense.kiokoman.home]/boot: sysctl -a | grep override
dev.vmx.0.iflib.override_nrxds: 0,0,0
dev.vmx.0.iflib.override_ntxds: 0,0
dev.vmx.0.iflib.override_qs_enable: 0
dev.vmx.0.iflib.override_nrxqs: 0
dev.vmx.0.iflib.override_ntxqs: 0

I will check on 2.5. Though reading this:
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=237166

If it has changed, the new values should be:
dev.vmx.0.iflib.override_ntxds="0,2048"
dev.vmx.0.iflib.override_nrxds="0,2048,0"

Edit: I tested on pfSense 2.5/ESXi 6.7 with the following in /boot/loader.conf.local
hw.pci.honor_msi_blacklist="0"
hw.vmx.txnqueue="4"
hw.vmx.rxnqueue="4"
hw.vmx.txndesc="4096"
hw.vmx.rxndesc="2048"
net.link.ifqmaxlen="8192"

I was able to see multiple queues. I don't believe these are supposed to show up in sysctl.