Buy the a6400 ifyou shoot mostly stills or want a camera that handles like a proper camera. The viewfinder lets you compose in bright sun where a screen washes out, the weather sealing shrugs off dust and drizzle, and its oversampled 4K30 actually looks a touch sharper than the ZV-E10’s cropped 4K. It’s the more versatile all-rounder, and it appears in our hybrid camera guide for exactly that reason.
Buy the ZV-E10 ifvideo is the point. The fully articulating screen flips to the side so it stays visible even with a microphone mounted on top, the controls are built for talking to the lens (there’s a background-defocus button and a product-showcase mode), and it’s lighter. You give up the viewfinder and weather sealing, and the 4K is cropped — fair trades if you shoot off the screen. It’s our long-standing pick in the vlogging camera guide.
Because both use the same E-mount and sensor, you can’t make a bad choice on image quality — decide on the viewfinder-versus-flip-screen question and buy accordingly. And whichever you pick, the best next purchase is a lens: our Sony APS-C lens guide covers the first upgrade for either body.
If neither of these quite fits because what you actually want is in-body stabilization and 4K60, the comparison to read next is a6700 vs a6400— the flagship adds both, plus a vari-angle screen that clears a top-mounted microphone, which is the one thing the a6400 genuinely cannot do.