Why do you need the flash in movie mode. The image sensor does not have a fast enough read out speed. To allow flash photography with the electronic shutter. Only the Canon EOS R3 supports flash photography with the fully electronic shutter in stills mode.
If you need to add lighting for videos, you need need to use a continuous light source. Not a flash/strobe.
A flash works for a still photograph. Recording video means the camera is recording 30-60 still frames per second. A flash cannot recharge that quickly. Use a video light with continuous output.
You can cage up a M200
And add a LED Video light. Many are small and rechargeable. Put a little handle on there and start shooting.
Its up to you how far you want to go with it.
Bay Area - CA
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