For people who this is not working for, make sure you followed this guide
https://samilops2.gitbook.io/vita-troubleshooting-guide/shader-compiler/extract-libshacccg.suprx
Usbloader GX has themes that you can install, if you don't have a theme installed on usbloader gx, then disregard this, but if you do have a theme installed on usbloader gx, and it is not made correctly, it can prevent usbloader gx from starting, it hangs at the startup screen.
Sometimes a bad theme will hang usbloader gx
I think you have to delete the ini file, it's been a while since I had to do that, so I'm not sure exactly
You could always mod your joycon to have a switch in between the battery and board to see if that works, but I think the batteries are meant to discharge after a while of not using them so the batteries don't have problems when storing your device.
Ah, yes, portrait mode, surely the best way to film a row of people. If only there were some way to fit a wider shot, at the expense of height... if only...