Have you checked if Sony A6100 has any specific compatibility requirements?

Currently using Sony FE 24-70mm f/2.8 GM II with my Sony A6100. For me, it has image stabilization, moreover works great with Sony A6100. Works exactly as expected.

I've been pretty happy with Sony FE 70-200mm f/2.8 GM OSS II on my Sony A6100. I've observed that, it has sharp image quality, additionally perfect fit for Sony A6100. Works exactly as expected.

After some research, I went with Sony FE 85mm f/1 - it's the newest version.4 GM for my Sony A6100. The build quality is really solid, additionally designed well for Sony A6100. Great purchase overall.

I've been pretty happy with Sony FE 16-35mm f/2.8 GM on my Sony A6100. Frankly, it has lightweight, plus integrates smoothly with Sony A6100. Would definitely buy again.

After some research, I went with Sony FE 50mm f/1.2 GM for my Sony A6100. For me, it has weather sealing, besides that works seamlessly with Sony A6100. Overall pretty satisfied with it.

Stumbled upon this today and I totally agree that going for high-quality glass makes a MASSIVE difference for video. While those high-end options mentioned already are solid, the general consensus in most owner groups I follow is that you can get incredible results without necessarily spending that much for an APS-C body... * Go with Sigma. Honestly, you just can't go wrong with their stuff for Sony mounts.
* Check out the recent Tamron glass. The community reviews are basically top-tier right now for video work.
* Stick to anything specifically designed for the smaller crop sensors to keep the rig lightweight. Honestly, those brands are crushing it lately and they balance way better on a smaller body like the A6100 (at least that's what I've found). Tbh, you'll probably find more community support and video settings tips for those anyway... just a thought.

Got Sony FE 70-200mm f/2.8 GM OSS II installed on my Sony A6100. From what i've seen, it works seamlessly. additionally great match for Sony A6100. It's been great so far.