To clarify, the server is Ubuntu and the client is Vyos per your example; I view this the other way in that Ubuntu is the client connecting to the Vyos server for connection to the LAN but that may not matter. Should the interface ‘dummy’ in your example be ‘eth1’? That is eth1 on Vyos is 192.168.8.9/24 and from the Ubuntu machine I need to be able to ping 192.168.8.6.
Regarding the settings on the Ubuntu machine:
$ sudo sysctl net.ipv4.ip_forward
net.ipv4.ip_forward = 1
$ sudo ip route get 192.168.8.6
192.168.8.6 dev wg0 src 10.10.1.26 uid 0
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