Archlinux

sudo pacman -S wireguard-tools
#sudo pacman -S wireguard-dkms  # built into linux kernel >5.6

FreeBSD

pkg install wireguard

# /etc/rc.conf

gateway_enable="YES"
wireguard_enable="YES"
wireguard_interfaces="wg-netwkA wg-netwkB"

service wireguard start