OpenVPN сервер

https://openwrt.org/docs/guide-user/services/vpn/openvpn/server

https://openwrt.org/docs/guide-user/services/vpn/openvpn/client

https://openwrt.org/docs/guide-user/services/vpn/openvpn/extras#multi-client

RNDIS

https://www.reddit.com/r/openwrt/comments/z40glt/use_rndis_usb_dongle_for_wan_connection/