As the title says, I have a condition that causes my body to severely shake and twitch, especially my hands. This mostly happens when I’m anxious or nervous, or just very excited. As you can imagine, this really messes up my aim and cause...

Just your agent's fist. Nothing else. Two fists would also be cool. Maybe boxing gloves? Left click would be a slap and the right click would be a right hook that swings across your screen. Also a plus could be a spiked glove of some sort....