Which H.265 for YouTube?

YouTube prefers H.264 video codec.
So, do I use Shotcut’s h264_amf or h265_nvenc settings?
Thank you.

Just click YouTube on the presets, then Export. The preset selects the appropriate settings for YouTube for you.
Shotcut 18.07.02

Sweet! Almost too easy! Thanks!

Are there any suggestions for Vimeo?
With Vimeo there is the additional problem that they only accept a maximum file size of 500 MB, and I’ve had problems with the YouTube presets.

Become a plus plan member if you need to upload larger high quality video.
You can lower the quality of your exports in an attempt to keep the data size low, but the results may not be pleasing.

Thank you. Yes I had to reduce the resolution drastically. Somehow the h.265 video codec didn’t produce a video, there was just a black screen with the audio playing.

Works fine here, but maybe your video player doesn’t support HEVC? (WIndows Media Player for example will just give a black screen)
I use PotPlayer.

VLC, should be OK, didn’t work though.

Yep, I just downloaded the latest VLC and it works just fine.
Problem appears to be with your computer.

Here’s a clip I just shot on my phone of some Curlews in the back yard.
Exported from Shotcut 18.07.02 to 1280x720 using the HEVC main profile preset (libx265)
60% Quality. GOP 149 (default) B frames 3, Quality based VBR.
Download it and see if it plays correctly for you.