ufw - Ufw stands for Uncomplicated Firewall, and is program for managing a netfilter firewall.
GlassWire - Visualize network activity in detail, get notified when new apps access the network, look out for...
ferm - ferm is a tool to maintain complex firewalls, without having the trouble to rewrite the complex...
Windows 10 Firewall Control - Windows 10 Firewall Control: simple and exhaustive solution for applications network activity controlling and monitoring.
Emsisoft Online Armor Firewall - Emsisoft Online Armor Firewall is a freemium online firewall protection system by the Emsisoft that is based on the own independent protection technology of the Emsisoft.
TinyWall - Lightweight and non-intrusive firewall