A dot of dust appeared in a corner of the sensor... and there's no easy way to (phisically) remove it.

If the teardown is simmilar to the Mavic 2 you can get access to the sensor from the rear of the camera, and then there are a buch of screws that hold the sensor in place, the problem is that putting the sensor back in place is not that easy because DOF, in the image plane of the lens is super narrow, so not going to do it unless the problem becomes more obvious (dust in the middle of the sensor).

If the sensor is prone to get dusty (AKA, not sealed)... why not implement an autocleaner like in every single DSLR out there? My 2012 DSLR has inbuilt cleaning lol.

DSLRs employ a cleaning device because the optics are open to the air when changing lenses. The DJI drones do not have the sensor open to the air, therefore a cleaning device is not necessary, or it shouldn't be.

Hello there Huginn Kenningar. I am sorry for the trouble tis has caused and thank you for reaching out. DJI do not recommended dismantling or taking apart your DJI Air2S. This process might affect your the said DJI drone while in use and can void the warranty as well. In addition, in case that you fill that your DJI Air 2S is not working properly on your next flight. It would be best to contact our DJI support team at https://www.dji.com/support for further assistance. We have a team that will do there best to check the said DJI drone and give out the best resolution for this issue. Thank you.

The drone works well... and I'm not going to return a drone just for a dot of dust in the corner of the sensor, it's not that dramatic anyways, it's more of a "what has been seen cannot be unseen" kind of thing. Hopefully it will move out of the sensor by it's own.

As a photographer I'm used to deal with dots of dust in the sensor (never manually cleaned the sensor of my Canon 6D XD), but being a full electronic camera without mechanical shutter or moving diaphragm that can't be opened I didn't expect it to happen.

By checking the videos and photos It appeared during a battery swap a few days ago, and nothing special occured; landed without the dot and then took off with the dot.

At the begining I thought it was on the lens, so cleaned it and checked it, but then I realised it was inside.