no need for a switch, you can get 5$ injection power supplies. https://www.roc-noc.com/mikrotik/routerboard/power/rb-p54.ht...

BTW, mikrotik is a very nice platform for geeks, en attendant Godot (a high load open source linux based router distro. Yes I know of openwrt, but that's kind of limited hw, hackish and prosumer? )