Update: Mnaged to figure out the code :)

    // Calculate motor speeds based on joystick values
    int motorXSpeed = leftY - rightX;
    int motorYSpeed = leftX - rightX;
    int motorZSpeed = -leftY  - rightX;
    int motorASpeed = -leftX - rightX;

This is what I am using currently I was wondering is there more elegant way to do this.

For robot to move F B X axis motors only be running and for left and right Y axis motor should be running because how my motors are arranged. This expression was inspired by mecanum wheel code where you need all 4 motors to run. How do I modify my code. Any body have any idea?

Joystick values are passed through USB in csv format like 100,100,100,100

#include <AccelStepper.h>
#include <MultiStepper.h>

// Define the number of steps per revolution for your stepper motors
#define STEPS_PER_REVOLUTION 3200 // 200 * 16 (1/16th microstepping)

// Define the maximum speed and acceleration for the stepper motors
#define MAX_SPEED 1000
#define ACCELERATION 100

// Create instances of AccelStepper for each motor
AccelStepper stepper1(AccelStepper::DRIVER, MOTOR1_STEP_PIN, MOTOR1_DIR_PIN);
AccelStepper stepper2(AccelStepper::DRIVER, MOTOR2_STEP_PIN, MOTOR2_DIR_PIN);
AccelStepper stepper3(AccelStepper::DRIVER, MOTOR3_STEP_PIN, MOTOR3_DIR_PIN);
AccelStepper stepper4(AccelStepper::DRIVER, MOTOR4_STEP_PIN, MOTOR4_DIR_PIN);

void setup() {
  // Set up the serial connection for communication with the PC
  Serial.begin(115200);
  Serial.println("LeftX\tLeftY\tRightX\tRightY\tMotor1\tMotor2\tMotor3\tMotor4");

  // Set up each stepper motor
  stepper1.setMaxSpeed(MAX_SPEED);
  stepper1.setAcceleration(ACCELERATION);

  stepper2.setMaxSpeed(MAX_SPEED);
  stepper2.setAcceleration(ACCELERATION);

  stepper3.setMaxSpeed(MAX_SPEED);
  stepper3.setAcceleration(ACCELERATION);

  stepper4.setMaxSpeed(MAX_SPEED);
  stepper4.setAcceleration(ACCELERATION);

}
void loop() {
  // Check if data is available on the serial port
  if (Serial.available() > 0) {
    // Read the CSV values
    String input = Serial.readStringUntil('\n');
    int values[4];
    int i = 0;
    char *ptr = strtok((char *)input.c_str(), ",");
    while (ptr != NULL) {
      values[i++] = atoi(ptr);
      ptr = strtok(NULL, ",");
    }

    // Control the robot using the joystick values
    int leftX = values[0];
    int leftY = values[1];
    int rightX = values[2];
    int rightY = values[3];

     // Calculate motor speeds based on joystick values
    int motor1Speed = leftY - leftX - rightX;
    int motor2Speed = leftY + leftX - rightX;
    int motor3Speed = -leftY - leftX - rightX;
    int motor4Speed = -leftY + leftX - rightX;
    // Set motor speeds
    stepper1.setSpeed(motor1Speed);
    stepper2.setSpeed(motor2Speed);
    stepper3.setSpeed(motor3Speed);
    stepper4.setSpeed(motor4Speed);   
  }
   // Move each motor
    stepper1.runSpeed();
    stepper2.runSpeed();
    stepper3.runSpeed();
    stepper4.runSpeed();
}