You could try splitting the install.wim file into pieces that are less than 4GB each, then copy those files onto USB or make an E2B drive. Google for split wim or swm. If the ISO contains more than one edition of 10 (Home, Pro, Enterprise, etc), then you can delete the file called ei.cfg in the \sources\ folder, so that Setup will allow you to choose the edition you want. I'm wondering, where did you get a 10 ISO that is over 5GB? Is it 100% official, or modified (pirated, had updates/drivers integrated into it, etc)? I don't think Microsoft would release a 10 ISO that has an install.wim/install.esd larger than 4GB, because this would make it difficult to boot the installer in UEFI mode, in which case FAT32 is generally required.
Edit: If your ISO has an install.ESD in \sources\, then you may need to decrypt it first, then convert it to install.wim. Then you can split the WIM into smaller pieces. ESD Decrypter can do both of these.
http://www.easy2boot...per-flash-drive
Read method 1 in the section called "UEFI booting: How to add Windows 7/8/10 installers with >4GB Install.wim files". There are other ways you can do this but I think that splitting the wim then creating an E2B drive from files, will be the easiest way. Make sure you read the part about splitting the WIM into 3000MB chunks, you can't just use any size or you'll hit issues. I found this out a few years ago and was searching for the info so I could post a link, but happened to find it on E2B's pages. I had tried to install 8.1 with a >4GB WIM and got the same issue as you. Also, at any points on the linked page that steve6375 refers only to Windows 8/8.1, it will also generally work with 10.