How to stop erroneous signals on startup of an RF circuit
Various circuits can achieve this, from a simple resistor in series with a supply combined with a large capacitor to ground after this resistor to ICs that are built for this specific purpose. My suggestion would be the following:

A simple PMOS in series with the supply. Using a large RC timeconstant (where 'large' means long enough for your ESP to start up before the gate-source voltage of the PMOS is high enough to turn it on) at the input could be used. 

At startup the capacitor is empty, and thus the gate-source voltage is zero, the transistor is off. The resistor can then charge the capacitor, and the transistor will turn on, connecting power to your switch circuit.







simulate this circuit &ndash; Schematic created using CircuitLab