I just found out that after reducing the resolution of the clear stream in my RLC-820A from 3840x2160 to 2560x1440 (with 6144 bps, may not be relevant), it started producing h264 videos. I tried reducing the video size to speed up converting the h265 videos to h264 with ffmpeg, just to realize it had nothing to do anymore at all.
@Reolink-Lorenz it would be really helpful if this were documented in the camera's settings page next to the stream resolution setting.

I just found out that after reducing the resolution of the clear stream in my RLC-820A from 3840x2160 to 2560x1440 (with 6144 bps, may not be relevant), it started producing h264 videos. I tried reducing the video size to speed up converting the h265 videos to h264 with ffmpeg, just to realize it had nothing to do anymore at all.
@Reolink-Lorenz it would be really helpful if this were documented in the camera's settings page next to the stream resolution setting.