A Pre-Match Action is primarily what the robot does before the match, but it is also these different movement types:
"READY": When the player selects a robot to fight, it goes to a screen where it shows the robots' stats, and shows them both on either side of the screen. The Pre-Match Action selected will determine what the robot does when the player selects the button to start the match.
STAT SCREEN: On the screen mentioned above, the Pre-Match Action determines what the robot is doing before the start match button is selected.
BEFORE MATCH: After the player starts the match, each robot has their own brief cutscene where the robot shows off a little. The Pre-Match Action determines what this is..
"BELL": This is usually the aftermath of "Before Match", or is based on what the robot does before the match.
AFTER MATCH: The robot that wins always has another cutscene based on what they do before the match.