Create a bootable Windows 10 USB on MacOS

windows_10_bootable_iso.sh

# Download the Windows 10 ISO
wget -O ~/Downloads/Windows10.iso https://software-download.microsoft.com/db/Win10_20H2_English_x64.iso?t=5f918d78-0088-47d5-adf9-8ccab64f2d3d&e=1604157841&h=675f0ae3a5a95da69c777d0d7031b8ec

# Mount the downloaded Windows 10 ISO
hdiutil mount ~/Downloads/Windows10.iso
# /dev/disk2          	                               	/Volumes/CCCOMA_X64FRE_EN-US_DV9

# Insert the USB stick (Minimum 8GB)

# Find the USB volume
diskutil list

# /dev/disk3 (external, physical):
#    #:                       TYPE NAME                    SIZE       IDENTIFIER
#    0:     FDisk_partition_scheme                        *16.4 GB    disk3
#    1:                 DOS_FAT_32 BOOT                    16.4 GB    disk3s1

# Erase the volume
diskutil eraseDisk MS-DOS "BOOT" MBR disk3

# Copy the files from the ISO to the first partition except for the 4gb one
rsync -av --progress /Volumes/CCCOMA_X64FRE_EN-US_DV9/ /Volumes/BOOT/ --exclude sources/install.wim

# Split the install.wim file into several smaller files so that they fit on the FAT32 partition
split -b 3700m /Volumes/CCCOMA_X64FRE_EN-US_DV9/sources/install.wim /Volumes/BOOT/sources/install.wim

# Unmount both the USB and ISO volumes
diskutil unmountDisk /dev/disk2
diskutil unmountDisk /dev/disk3

# Plug your usb into your other computer and install Windows
# It will complain that install.wim is not found
# Select Repair your computer -> Troubleshoot -> Command Prompt

# The diskpart commands below are from
# https://www.tenforums.com/tutorials/95941-diskpart-how-partition-gpt-disk.html

diskpart
list disk
# Choose the disk you want to format
# Disk ###  Status    Size    Free    Dyn Gpt
# --------  ------    -----   ------  --- ---
# Disk 2    Online    953GB   1024KB      *

select disk 2
clean
convert gpt

create partition efi size=100
format quick fs=fat32 label="System"

create partition msr size=16
create partition primary 
shrink minimum=450

format quick fs=ntfs label="Windows 10"
assign letter="W"

create partition primary
format quick fs=ntfs label="WinRE"
set id="de94bba4-06d1-4d40-a16a-bfd50179d6ac"
gpt attributes=0x8000000000000001

# Copy the files to the new partition
xcopy F:\ W:\ /f /j /s /w /z

W:
cd sources
# Combine the install parts into a single file
type install.wimaa install.wimab > install.wim 
del install.wimaa
del install.wimab

# Turn off the computer and remove the USB, then start it again and install windows