With 600D you are stuck to 1620x912 in video mode embedded in 1080i59.94 8-bit. Black borders around and you have to crop and - maybe - scale up.
200D HDMI stream with ML is clean with MF but AF will still draw a focus rectangle. But at least true FHD via HDMI.
AF with 600D in liveview: Phase detection only. Focus hunting galore. 200D comes with usable DPAF.
I prefer 250D for streaming. Dual display support, no 30 minute limit for HDMI out (but cam display will go dark until some button action).
AF with 600D in liveview: Phase detection only. Focus hunting galore. 200D comes with usable DPAF.
I prefer 250D for streaming. Dual display support, no 30 minute limit for HDMI out (but cam display will go dark until some button action).