Hi Nathan, correct - FAT32 only supports file sizes up to 4GB - BUT there are work arounds.
What I think is the easiet and best solution:
1. if you use your switch near you PC, then download the NUT.EXE version 1.2 from g
ithub.com/blawar/nut/releases
2. run the NUT.EXE, make the popup window larger so you can see the "select folder" button and section in the top left of the window - click in there and point it to the folder where you have your NSP and XCI files on your windows PC.
3. Nut will scan all the files and you can now install files larger than 4GB direct over USB cable to the switch - but you will need to download tinfoil version 1.55 from the tinfoil.io web site and copy the files from the ZIP file to your SD card.
4. run the tinfoil v1.55 installer on your switch and you'll now see all the files on your PC - you can directly install the NSP files on the PC to your SD card or the emuNAND. (eg: it took me about 4 minutes to install Skyrim over the USB cable like this).
The next best solution (also useful if you have a large XCI collection):
1. if you have a USB C to USB female adaptor (mine cost about $5 from my local PC store.. basically it's an adaptor to plug into the switch which then has a normal female SUB socket) plug it in, then plug in a USB stick or USB HDD which is formatted as EXFAT and have the large files on the USB stick. Install the files using tinfoil v1.55 as per listed above and you can install the NSP or XCI file to your SD card or emuNAND.
2. I have a western digital 4TB 2.5" self powered (elements series, I think.. it's rectangular with 'squarish' edges and a dark blue colour) which I connect to the USB adaptor and then I can mount XCI and play them direct from the USB HDD - whether in hand held or docked mode.
The least best solution (in my opinion if you don't have access to a PC to run NUT, or a USB stick and adaptor)
1. split the large files into 4GB parts - there are a number of tools on this site which can do it.. tinfoil v1.55 supports installing of split NSP files as well.. so copy the files to your SD card and then install as per normal.. you will need to delete the files from the SD card after you install them.