Please see images. Its my network map on first image, and firewall settings of OpenWRT router in the second screenshot.
Short description: Any 10.7.0.xx and 10.8.0.xx clients can access any 10.8.0.xx and 10.7.0.xx clients
Clients on 10.7.0.xx can access the router (10.7.0.51).
For 10.8.0.xx clients, the router does not respond to requests.
Question - how to make the router (10.7.0.51) respond to clients 10.8.0.xx?
Long description: Mobile phones with OpenVPN client app have acces to mobile phones with WireGuard client app. Thets why, i think - VPS have correct configs.
But OpenVPN clients not have acces to Wireguard client on the OpenWRT router.
IP 10.7.0.51 response only to 10.7.0.xx requests. But not response to requests from 10.8.0.xx clients.
You probably need to add some routes. You might need to push a route to the OpenVPN clients for 10.7.0.0/24 via the tunnel. Make sure that you are allowing forwarding between the networks on the VPS. Then add a route on the OpenWrt router for 10.8.0.0/24 via 10.7.0.1.
On the previous router, with exactly the same version of OpenWRT, I managed to solve this problem when I was in the Wireguard access list (I have an extension installed - so that traffic is routed through the WAN by default, and certain IPs are routed through the VPN). But now it doesn't help. I disabled the extension.
Added to peers wireguard:
A very strange thing is happening with wireguard. If I specify peers 220.127.116.11/1 and 0.0.0.0/1. Then wireguard starts working as the default gateway. I unchecked the "default gateway" wireguard interface settings and gave it a metric number higher than the WAN metric number. But with these peers settings, wireguard continues to work as the default gateway. At the same time, I have the access to the router I need from clients 10.8.0.0/24, but I do not need wireguard as the default gateway
Now I will fix the settings after some experiments and do what you suggested