I want to set up a VPN that uses the client’s IP when sending data out of the VPN server. I am able to use either OpenVPN (open-source edition), or Wireguard.
This feels like a XY problem. To be able to provide a useful answer to you, we’d need to know what exactly you’re trying to achieve. What goal are you trying to achieve with the VPN and what goal are you trying to achieve by using the client IP?