I want to know if I can use a diode in series with the power source that will power the Node MCU to protect Node MCU from reverse connection or short circuit
Yes (but there will be that pesky diode forward-voltage drop).
Yes you can use a diode to remove the risk of reverse polarity. The cost, however, is a voltage drop dependent on the diode type. A schottky is the better type with only 0.4 volts.
A p-channel mosfet is generally a better solution and the voltage drop is negligible.
There is already a common 4007 reverse protection diode between 5volt USB and RAW/V-in.
So not a problem to run the NodeMCU's '5volt rail' on ~4.3volt.