That particular adapter doesn’t seem to be supported on macOS versions past Yosemite (10.10). Per the tech specs listed on the page for the TP-Link UE300, it lists:
Plug and Play in Windows (XP/Vista/7/8/8.1/10), Mac OS X (10.9/10.10), Linux OS. NB: stuurprogramma nodig voor Mac OS X (10.5-10.8).
The text “stuurprogramma nodig voor” is Dutch and translates to “driver needed for.”
This appears to only have built-in support up util Yosemite and an external driver is necessary for OS X versions Leopard through Mountain Lion (10.5 through 10.8).
That particular USB driver uses the Realtek RTL8111 chipset which seems to have been dropped from macOS versions past Yosemite as evidenced by this Hackintosh blog post where the author laments the condition of the existing drivers and the need to port the Linux driver to macOS.
Your best bet is to get a new, compatible adatper.