Yes, you can connect two PoE switches together, and this is a common scenario in many networking setups. 3af standard, which specifies the maximum power delivered over Ethernet cables. 4 watts of power per port, while PDs can consume up to 12. PoE switches are commonly used for simple devices. It's 8 ports and about 70 bucks on the jungle site. If you want to save a few bucks, for $30 (and if they actually have them available), Unifi's Switch Flex Mini is 5 port POE powered without pass through. While it is quite rare and has power limitations (as incoming power has to be split accross child connections). Such a device enables its tasks to be performed as a standard Ethernet switch, but in addition to that it can give supply power.