Activism channels are all about outrage - righteous outrage for the best causes, echo chamber outrage for others. Activist influencers are those who use their platform to bring attention to their personal causes, explaining the problems and perils of the day in short, easy-to-digest sound bites or video clips. They organize protests, lead demonstrations, and provide real-time commentary on the events they witness. This tends to put them in the middle of a lot of police actions and riots.
Underground activists tend to be anti-corporate, but the corpos sponsor plenty of their own influencers who exist to counter those claims, waste time with "both sides" arguments, and actively promote fake news.
Front Line Training
When you join the Channel of the Activist at 3rd level, you gain proficiency with medium armor, shields, and military weapons.
Combat Inspiration
Also at 3rd level, you learn to inspire others in battle. A creature that has an Influencer Inspiration die from you can roll that die and add the number rolled to a weapon damage roll it just made. Alternatively, when that creature is the target of an attack, it can use its reaction to roll the Influencer Inspiration die and add the number rolled to its AC against that attack, after seeing the roll but before knowing whether it hits or misses.
Extra Attack
Starting at 6th level, you can attack twice instead of once whenever you take the Attack action on your turn.
Combat Tech
At 14th level, you have mastered the art of using tech and weapons at the same time. When you use your action to cast an influencer tech, you can make one weapon attack as a bonus action.