the 25 minute limit for recorded video is related to the size of the internal storage. The storage is NOT a removable microSD so you can’t increase the storage. There is no internal microSD card so you can’t increase it even if you take your camera apart.
In the document below for the THETA S, I tested saving the live stream to file using OBS, then using Adobe Premiere Pro in VR Mode to edit the file, then upload it to YouTube.
I have NOT TESTED THIS with the THETA V, but it is is a probable solution. You may need to inject metadata back into the video file, though I did not need to do this in my test. If you do need to inject metadata, it is easy. I think someone will test this in the coming week, so if this is something you need, then you should wait for someone to confirm that it works. In my personal opinion, it’s likely to work.