h265 - what is possible?

Hello,

I have some Reolinks and quite happy with the quality.

But I am not sure about the topic "h265".
I understand, HomeKit does not support this codec.
NVR should. When I set the "Local Recording Stream" to h265 - it seems al recordings are done in h265 when I scrub to the history, but it seems there is no more event detection.
With which of the scrypted streams is the detection done?

If I would not use HomeKit. Would it be possible to use for all streams the h265 streams?

Thanks!