Ok... i think everything is actually okay for IPv4, but your internet access is not working from the vlan network because you're not allowing vlan > wgwan forwarding. With the WG tunnel running, all traffic is routed by default through that tunnel... so if your firewall doesn't allow it, no traffic will flow (solution for this is PBR).
If you disable your wireguard interface (and restart the wan interface), you should have access to the internet. Alternatively, you can allow vlan > wgwan forwarding like this:
config forwarding
option src 'vlan'
option dest 'wgwan'
and that will allow internet access. Once this has been proven out (either method), you can consider your IPv4 to be working as expected.
Your next step will be to install policy based routing and define rules to route the lan and vlan as desired.
On IPv6, I am not an expert on this. My recommendation would be to mark this solved (once you've established that IPv4 is working properly based on the above discussion), then open a thread about IPv6 (which will be purely related to the Pi's configuration), and if you need help with PBR, you can open a thread for that, too.
When you're ready....
If your problem is solved, please consider marking this topic as [Solved]. See How to mark a topic as [Solved] for a short how-to.