You need madVR and can choose what you want:
- passthrough the HDR metadata to the screen (OSD will show HDR)
- tonemap the HDR metadata with madVR (OSD will
not show HDR, becuase the TV isn'T receiving HDR metadata anymore, because madVR did the tonemapping)
MPC-BE can also convert HDR to SDR with internal filters, without the need of madVR and MPC-BE development is very active. See its thread for more infos or questions:
Media Player Classic - BE Win32/x64
Here you can download latest Nightly build, don't worry -> rocksolid
https://yadi.sk/d/r7JYQ2NjHvE4lA/Beta/1.5.4
https://yadi.sk/d/hlf1lfC8mKU58