HEVC corresponds to ‘x265’ and ‘x265-libs’. Have you installed them?
Anyway, I installed the following:
dnf install libavcodec-freeworld gstreamer1-vaapi gstreamer1-plugins-base gstreamer1-plugins-good gstreamer1-plugins-good-extras gstreamer1-plugins-ugly-free gstreamer1-plugins-bad-free gstreamer1-libav gstreamer1-plugins-bad-freeworld gstreamer1-plugins-ugly gstreamer1-plugin-openh264 pipewire-gstreamer svt-vp9-libs x265 x265-libs