what is the difference between transmitting and receiving leds(circled) connected to sensor board and ir emitter and receiver diode shown in second pic?Will the output change it i replace the former leds by latter?if yes then how? Second pic is from https://www.amazon.in/CENTIoT-Universal-Infrared-Emission-Receiver/dp/B071NK3KD4/ref=sr_1_10?keywords=ir+leds&qid=1554913735&s=gateway&sr=8-10
The dark coated LED has a filter, that filters out other wavelengths except for the one, that it is specified for. The clear one doesn't have this coating, since it is used for sending. If you replace the coated one by an uncoated version, the results may get worse, when other IR sources are present (like the sun).
Also the specifications of the LEDs might be different, we can only speculate about that without knowing the part numbers of the used LEDs.
All in all it might not be a good idea to exchange the LEDs for one another. You haven't stated, why you want to do this.