I was wondering if its possible to use the mini 2 just as a stationary camera for continuous video recording, but I cannot find a way to power it via usb while the camera is running. Is there a way to connect it to a power bank and use it as a camera for a second video angle without flying? And is the recording time limited? Thanks for your help!

Of course the recording time is limited by the capacity of your SD-card.

I could be wrong but i think it might be a new file every 2gb maybe 4gb

I think I would be concerned about the heat build up due to lack of airflow.  I believe the Mini 2 is designed to be cooled from the airflow when flying.

Bashy Posted at 4-1 07:41
I could be wrong but i think it might be a new file every 2gb maybe 4gb

It appears to be every 3.8gb.
Funny thing that I noticed with my new Air 2 is that it doesn't create new files. I had 1 video I recorded that resulted in a single 11gb file.

Hello there. Good day and thank you for reaching out. For additional reference the maximum capacity of a single file will not exceed 4GB. If exceeded, the recording will be stopped, and a new recording will be started. In addition, the maximum file size of FAT32 is 4GB. Hence, a file that is larger than or equal to 4GB will be divided, otherwise, the file may be lost or abnormal and cannot be read. Although exFAT allows a larger file size, the larger file may be damaged due to abnormal power-off and SD card removal, or even cannot be recovered. So the storage of the camera is 4GB regardless of the file systems. So it is normal the video will be split if it reaches 4GB. In addition kindly please use a supported microSD card on your DJI mini 2 for compatibility and reliability purposes. Thank you.

Aside from the video size and risk of cooking the drone as far as I am aware the drone's battery will not charge via any means if the drone the battery is in is switched on.

If you find away to do that, you want to have props running, otherwise it will overheat quickly, I get warning while file transfer as I forget to disconnect. Wondering what would happen if you plug it while props are already running?

Thanks! I tried to record a video for a short time while resting on my table and indeed - it gets quite hot. So maybe not a good idea. I think with my older mavic 2 this was not an issue.

Direct the output of a fan over it.