RTMP Protocol and H265 Codec - Challenges and Solutions

Real-Time Messaging Protocol (RTMP) is a communication protocol for streaming audio, video, and data over the Internet. It was originally developed by Macromedia for their Flash Player, which later became Adobe Flash Player after the company was acquired by Adobe. 

RTMP protocol itself does not support H265 codec. If you want to use RTMP to push H265 video, you must make the playback end (player) compatible. If your live broadcast is only played on your own platform, it is easy to do. However, if it can be broadcasted to any platform, it cannot be guaranteed that other platforms can also support FLV (H265) decoding. 
You can use FFmpeg to extend the FLV protocol to support RTMP pushing of H265 video.

Oupree Video Encoder support H265 rtmp to the media streaming server which with H265 supported rtmp.