In my Fly More box I recieved one USB-C to USB-C cable (about 18in) and another cable, USB-A female to USB-C.

Does it matter which you use to connect to your phone to apply firmware, etc.?

I have seen some vidoes in which they use the USB-A to USB-C.

I didn't see anything in the instrtuctions.

Not really

I got a couple errors updating the firmware but I don’t think they were cable related but it finally finished.

I tried a few dozen times with various (working) usb-a to usb-c cables I own, from Samsung, Sony, and no name with their DJI Assistant App. Couldn't connect to the app. Tried my own USB-C to USB-C (js aux) and another and no dice. The phone seems less picky the belkin cable I tried on the first round (A to lightning) has worked every time.

For whatever reason it connects consistently with 100W / 480mbps cables I got from ugreen a while back.
https://www.ugreen.com/products/ugreen-usb-c-to-usb-c-cable-3ft-6ft-10ft

tl;dr it's weirdly picky but the dongle isn't necessarily your friend.

Hi, swooshdave. Thank you for reaching out. You may use whichever you prefer. USB-C to USB-C can be used for PD (Power Delivery) protocol for fast charging. If your computer has a USB-C port, it can also be used for data transfer or firmware updates. USB-A to USB-C can be used for connecting to a computer for data transfer or firmware updates. If your computer has both USB-C and USB-A ports, you can use either indiscriminately. Hope this helps.

swooshdave Posted at 4-15 16:07
I got a couple errors updating the firmware but I don’t think they were cable related but it finally finished.

Hi there. We're sorry to here about this. Are you still having trouble updating the firmware? If yes, can you please share with us the details for us to check?

DJI Gamora Posted at 4-19 07:01
Hi there. We're sorry to here about this. Are you still having trouble updating the firmware? If yes, can you please share with us the details for us to check?

No, it seems to be working fine now.

When an USB device you're connecting to can be both a USB host and an USB peripheral, some Android devices have trouble negotiating which of the two (phone and goggles in your case) is the host device, so in that case you need the OTG adapter (USB-C to USB-A female you mentioned) on the side of device you want to be host (usually your phone, and you can usually tell if goggles become host because your phone will try to charge itself). Most phones can just use a straight USB-C to C cable though. Or if you have an iPhone older than 15, just use an USB-C to Lightning.

swooshdave Posted at 4-19 21:20
No, it seems to be working fine now.

Thank you for the reply. Glad that you were able to update the devices. Should you need further assistance, please don't hesitate to reach us again here at DJI Forum.