DJI Mic Mini is recommended.

I use DJI MIC 2, and it works well all the time.

I highly recommend checking out the Rode VideoMicro compact on-camera microphone. Some key benefits:

• Very compact and lightweight, perfect for the small Sony a6600
• Provides a significant upgrade in audio quality compared to the built-in camera mic
• Plugs directly into the camera's mic input, no batteries required
• Includes a shock mount and furry windshield for reducing handling noise and wind noise
• Affordable price point around $60

I've been using the VideoMicro on my a6600 for vlogging and it works great. The audio is clear and it's very easy to use.

If you're serious about audio and don't mind a slightly larger setup, the Sennheiser MKE 600 is an excellent choice. It's a professional-grade shotgun mic that provides superb audio quality. You'll need an XLR to 3.5mm adapter to use it with the a6600, but the results are worth it if audio is a priority for your work.

MKE 400.