I used to play it a lot when it was cool.
I recommend https://wormhole.app for the purpose. Drag, drop, leave the tab open.
Haven’t heard anything, just from memory of my own testing. Looking back at my notes I see a 40-50% speed up with VideoToolbox compared to x265 on M1, but at a lot crappier quality.
I haven’t tested in quite a while, though. I wrote off doing encoding on the M1, as my AMD cards are a lot faster (and produce better results).
It’s hard to beat a GPU in HEVC encoding performance. SoC:s have comparable performance to dGPU:s in that regard. A used zen/zen2 laptop might be a cheap and tiny workhorse for the purpose. I have a zen/vega10 matebook 2020 that does 1080p at around 2.5-3x real-time at high quality presets. No doubt it could do 4k at faster presets.
With the hardware in my arsenal I’ve found that AMD>Intel>nVidia, at least quality wise. VideoToolbox on Mac is down there with nVidia, and Apple silicon being pretty slow at it compared to software x265 on the same machine.
I’ve been trying to convince my boomer wife to try affinity. She works mostly with print, and it seems like a good fit to me.