Im afraid nothing will work as a zone splitter. If you have the cores then you can go more conventional and use eol. If not your looking at an addressable tech like hkc
bear in mind that if using wifi and you loose power you will probably loose your WiFi and internet connection unless supported by a UPS
some of the app platforms support polling though
Assuming you have enough bandwidth you can run many cameras down a single link. You will just need the poe switch to be at the end of the cox run once its converted to Ethernet
You could use a control panel for this and adjust the bell time or a timer relay eg
https://www.securitywarehouse.co.uk/catalog/intruder-alarm-c-36/intruder-alarm-ancillaries-c-36_46/tkc-160-precision-timer-p-2664.html