I also have the GE800, and from what I know, the router supports WireGuard VPN both as a client and a server. However, not every VPN provider works equally well with router-based WireGuard setups. It’s best to choose a provider that gives you full WireGuard configuration details (like public key, private key, and endpoint), since these need to be entered manually in the router's interface. Some providers only support their own apps, which won’t work on the router directly. Several users have reported good results with Mullvad, ProtonVPN, and IVPN - they all provide simple WireGuard config files and are known to work reliably on many TP-Link routers. Also make sure your firmware is updated to the latest version, since WireGuard stability has improved in the more recent GE800 updates