Accessing two MPU-9250 DMP I want to use both IMU at the same time using the Sparkfun Library on a SAMD21 mini breakout board. Can anyone help?

The begin function is :

inv_error_t MPU9250_DMP::begin(void) {
  inv_error_t result;
  struct int_param_s int_param;
  Wire.begin();
  result = mpu_init(&amp;int_param);
  if (result)
    return result;
  mpu_set_bypass(1); // Place all slaves (including compass) on primary bus
  setSensors(INV_XYZ_GYRO | INV_XYZ_ACCEL | INV_XYZ_COMPASS);
  _gSense = getGyroSens();
  _aSense = getAccelSens();
  return result;
}
Sorry, but I'm not 100% sure of what you are trying to do, I don't understand 'both imu the' in your question.  I think you are trying to use two identical boards at the same time.  (If not tell me so I can edit my answer)

You will need to modify the library so the begin function takes a parameter.
That parameter for MPU9250_DMP::begin then identifies the address of the device, this will need passing to Wire.begin() I think (you'll need to check the Wire.begin() function, I can't).

That should let you create two different instances of the class.

MPU9250_DMP apple;
MPU9250_DMP banana;
apple.begin(0x68);
banana.begin(0x69);