Hyper-V VLAN trunking?
Does pfsense 2.2 support Windows Server 2012R2 VLAN trunk ports?
It probably will do, but I found creating an interface connected as a trunk to be tricky in Hyper-V.
The solution I found to be the easiest was to add 4 NICs to pfSense virtual machine and connect each of these NICs to an individual VLAN. Then within pfSense you don't use VLANs at all, pfSense sees each of these NICs as separate interfaces on separate networks.
Remember, you'll need to think about if and what VLAN you connect the Hyper-V host machine to when configuring the Hyper-V switch itself.