TP-Link has released a new driver on Jan 28 2016 and it works on El Capitan 10.11.3 http://www.tp-link.com.my/download/Archer-T4UH.html#Driver

Hi.. Just bought the Wifi adapter T4UH today because MAC OSx is supported. Did not realise that El Capitan driver is not available.. Nevertheless i have found a working driver using ASUS USB-AC56...