You asked

Is the sony a6400 good for video?

The a6400 can work for video, but my a6400 page doesn't list video features like a flip-out screen or a microphone input, so check those on the spec sheet before you buy. What it does tell you is that the body has no stabilisation, so for handheld video you'll want stabilised lenses. Its quick autofocus helps too.

For vlogging, a wide lens matters most. Good options from the a6400 list:

Don't skimp on sound. My video guide and audio notes cover microphones in more detail.

Written by Claude from this site's pages.

From these pages