1500ft 8 Port Long Range PoE+ Switch, PoE Extension with Continuous Run of cat5e/cat6, Fast Ethernet 10/100Mbps, 30W IEEE802.3at/af

The most reliable solution is the cable without daisy chain any active devices. 1500ft PoE+ Switch doesn't require PoE extenders in the middle. It is only the PoE adapter at the edge for return the signal over ultra-long distance. What you need to bury underground now is just the cable.
The 1500ft Long Range PoE+ Switch works with standard IEEE802.3 PoE/PoE+ IP devices only. The system will not work while your devices are passive PoE or non-PoE equipment. The switch needs to perform power handshake with your devices before it starts working.
One of the tricky things to extend the PoE is the power loss inline. There is always PoE loss during the transmission. The longer the distance, the more power loss will occur. You should pick the pure copper Ethernet cable instead of the CCA type.
PoE Standard IEEE 802.3af, IEEE 802.3at, IEEE 802.3bt, Legacy Bt, UPoE Networking Interfaces (8) 10/100 Mbps PoE Ports (2) 10/100/1000 Mbps uplink Ports PoE Port 1-8 (Only ports #1- #4 support 800m long-distance PoE, extra POE adapter for the other two long range ports are sold separately.) PoE Total 120W Power Supply 125W Max. Power Port (port #1-#4) 30.28W (328ft), 26.58W (984ft), 23.46W (1648ft), 17.56W (2500ft) Indicator PWR LNK/ACT PoE Network media (port #1-#4) 100BASE-T: UTP category 3,4,5 cable0500m 10BASE-TX: UTP category 5, 5e cable500800m Bandwidth 5.6Gbps Surge Protection Differential mode±2KVCommon mode ±6KV