DISCLAIMER: If you found this article you are either me (duh) or clever enough to use Google to find it and find all missing
pieces of information that you are still not aware about. I DON'T DO FREE SUPPORT OTHER THAN WHAT I NEED TO MYSELF AND MAKE
PUBLICLY AVAILABLE!

1 - Install Virtual Box, get an ISO copy of windows installation and open Bootcamp on Mac (Action > Download drivers) to get
the drivers for windows

2 - Create a "ramdisk" that will actually point to your external ssd. For this you need to know the disk (you
can simply type mount on terminal and figure out the disk number by yourself). After you know the number, type this in
terminal:

$ sudo VBoxManage internalcommands createrawvmdk -filename "windows.vmdk" -rawdisk /dev/disk(# of the disk)

2.a - In case you have an error, remember to umount the disk before trying to use it. Go google (or...:

$ diskutil unmountDisk /dev/disk3

and then repeat step 2.

3 - So, even after you have done 2.a and repeated step 2, you will need a second

$ diskutil unmountDisk /dev/disk3

4 - As soon as step 2 in completed, you may be requested to use the disk as a "timeblablab". This is horseshit. Don't use.

5 - Now open Virtual Box and create a new Vm for Windows, and choose windows.vmdk as the disk for it.

sudo /Applications/VirtualBox.app/Contents/MacOS/VirtualBox

6 - Start the VM, install windows.

7 - Install MacOS Mounty, so you can copy the downloaded drivers to the hard disl

8 - Start the "VM" and install the drivers

9 - Reboot mac holding ALT/Option key and see the SSD as a bootable option.

10 - You did it. Bitch!