How to Enable Communication Between Devices on Separate Wi-Fi Hotspots Through a WireGuard VPN?

I have a Windows PC set up as a server with a WireGuard VPN on 10.10.10.1/24 and a client connected from another PC with 10.10.10.3. I share Wi-Fi hotspots on both PCs separately (both using 192.168.137.1/24) and connect one device to a PC with IP 192.168.137.153 and another device to the other PC with 192.168.137.80. How can I make them discover each other? How can I make them ping each other?

From either device, I can ping the VPN server or client (10.10.10.x), but not the other way around, and I don’t know why.