1)The PSoC 6 anlaog routing and architecture is not similar to PSoC5. So you may not be able to use that AN while designing with PSoC6. Please refer PSoC6 Hardware Design Guide for reference. This document suggests the pins suitable for the component you are going to use. For example port 10 is dedicated for SAR ADC. Port 9 is next preferred port. This is because connection to other ports will include additional switch resistances on the path.
2) The same is true for CYBLE-416045-02 module. Port 10 is directly connected to the port and port 9 is the next option. The description you are suggesting is regarding the working of the ADC where the input is switched between the user selected pins. The ADC have connectivity to other pins at the expense of additional switch resistances.