Understand low power gate timer TPL5110, any alternates?

I was reading datasheet of TPL5110 it says "the TPL5110 has a unique One-shot feature where the timer will only power the MOSFET for one cycle."
I do not understand what does it mean by "One-shot feature" and "turning on MOSFET for one cycle" here what does it mean by one cycle?

I want to turn on ESP8266 by this timer i want to know which MOSFET would be suitable in the circuit

Is there any better alternate approach for same application?