How can I get Ethernet adapter and still be able to charge my tablet
Yes, but I have not found a single device solution that solves the problem. Utilizing multiple devices can solve the problem.

According to PoE Texas, you can combine the use of a USB to RJ45, Powered USB OTG Hub, PoE Splitter Micro-USB and RJ45. Finding a 10 Watt OTG Hub would be good for continuous use of a charging device.