qemu socket multicast not working

Running two qemu vms on the same socket multicast address:

  qemu-system-x86_64 -m 2048 -smp 2 -serial mon:stdio -display none -vga none
    -nodefaults -accel hax
    -netdev user,id=mynet0
    -device virtio-net-pci,netdev=mynet0
    -netdev socket,id=vlan,mcast=239.192.0.1:1235
    -device virtio-net-pci,netdev=vlan
    -device virtio-rng-pci
    -drive file=worker.qcow2,if=virtio
    -drive file=cloud-init.iso,format=raw,if=virtio

The two machines have a static ip on the socket network interface, 192.168.100.11 and 192.168.100.12, but are unable to reach each other. 

Is there additional configuration necessary on macos? Does this only work on Linux?

guest OS: Debian 10 (Buster)
host OS: macOS 10.15.2
qemu: 4.2.0