Did you enable forwarding via sysctl?
sysctl net.ipv4.ip_forward
This should report 1
Did you enable forwarding via sysctl?
sysctl net.ipv4.ip_forward
This should report 1
You only need the masquerade rule.
iptables -t nat -A POSTROUTING -s 10.11.13.0/24 -o enp3s0 -j MASQUERADE
The company behind pfSense is shady as hell:
https://opnsense.org/opnsense-com/
Also the complete and utter clusterfuck of an attempt to bring Wireguard into the FreeBSD kernel:
https://arstechnica.com/gadgets/2021/03/buffer-overruns-license-violations-and-bad-code-freebsd-13s-close-call/