With two ISPs on single openwrt router ,is it possible for wireguard vpn tunnel to do loadbalance on two WAN links
outbound VPN from your home to a VPN service?
Your options at home would be, to create 2 separate VPN Connections (one for each ISP) outbound and failover-balance them with mwan3.
Its a site to site VPN ,and in wireguard configuration i dont have the option to mention multiple ISP IPs