If you are running the VPN Director VPN clients on the router, then you will have IPv6 leaks, because they clients themselves do not support IPv6.
@RMerlin does not have access to an IPv6 ISP and without this it is not practical to do the work necessary to get this to work. As noted elsewhere you can disable IPv6 on the router, or just disable IPv6 on the devices routed through the tunnel(s).
If you want to use VPN providers who supports IPv6 then your current options are
connect via the provider's own clients (not the router)
move your VPN routing to a device that does support dual stack VPN routing (I believe it can be done on a pi, have never tried)
on a supported Asus device, run
@ZebMcKayhan's Wireguard Manager (WGM)
I use WGM, with dual stack and no leaks, but I also have a slow ISP (for fast links Wireguard will speed limit your whole network, not just the VPN tunnels)