I will try it but it is like putting a FIAT engine under a Ferrari To be honest with you, I may be simplistic since I do not know the code beyond VirtualBox but I think by just adding extra network adapters that allow vlan will fix this issue.
All your help has been very much appreciated, you guys make a difference by helping others like me.
Thanks PerryG, all the other cards have similar options but they do not allow you to setup the vlan, that I believe is another option itself. If you want to get more curious about it, you will find out that even Microsoft just released vlan on Windows 10 few weeks ago I was almost positive that vlan was a mature solution and critical in any environments. I would just need to wait in the mean time.
What I have found is that VLAN tagging for Windows guests is no longer supported.
For Windows OS'es after Windows Vista and 2012, Intel is no longer supporting ProSet on any of the VirtualBox supported network cards. The adapters work with the built-in base drivers, but Proset can't be installed.
@AlphaTech What exactly are you trying to do with vlans?
If you are working with only virtual networks there is no reason to use vlans. You can create as many virtual networks as you wish. The only time a vm NIC needs to know about vlan tags is when it is bridged to a physical network which uses vlans. As has been discussed at length in this thread, what matters in that case is whether the NIC driver in the vm handles vlan tags.
VirtualBox does not have anything built-in to support VLANs, and neither does Microsoft's Hyper-V. Hyper-V is VLAN aware and does recognize VLAN tags if your network infrastructure (routers a switches) can handle VLANs.
To be honest with you, I may be simplistic since I do not know the code beyond VirtualBox but I think by just adding extra network adapters that allow vlan will fix this issue.