The PCB is designed to have a set of mirrored pins for flipping it. Useful if you have a camera or a directional antenna. Also, since you could connect more sensors, you can have those looking in any direction:

For controlling the power (ESP32 and NRF) check the following solder pads (by default the ESP32 is powered by 5V and the NRF by 3.3V):

There is prototyping sections for 3 pin sensors. Since this sensors can have any pin ordering, be careful when plugging them on the right position:

Version 2

The same concepts apply on the version 2 with the exception that there is no prototyping area and each module is connected to their corresponding opposite side:

Complete pinout

For a complete description of the pins, check the first steps on how to make your DIY version of the board.