Hi,
AP features are independent of power input. more over you can power source other devices ( AP) through WAN port and it is compatible with 802.3at POE devices.
Yes we can bring up any other AP by hooking to WAN port of 170 series APs but we need to ensure the relevant configuration is done in the " Ethernet interface 1 port configuration" of the AP-Group going to provision the AP.
Hope you got some more clarity on this.
Please feel free for any further help on this.