There are “current command” and “torque” in the monitor value (graph function such in the analog monitor and MR Configurator2, etc.). What is the difference between them?

The “current command” is the command value for the current control (torque control) and the “torque” is the feedback value controlled by the current control (torque control).
The servo motor generates the torque according to the current flowing from the servo amplifier, and “current command” and “torque” will be in a relationship of command and feedback.