GCC:
MSVC:

A Cross-platform USB Module for Qt built around libusb-1.0 and libhidapi
Can be used as a library, or included directly into the project

• Bulk transfer
• Interrupt transfer
• Hotplug detection
• Device enumeration and filtering
• HID

Ubuntu (stable versions only)

sudo add-apt-repository ppa:fpoussin/ppa
sudo apt install libqt5usb5 libqt5usb5-dev

Windows
Check the releases page or appveyor build artifacts for binary archives

Unix
You need libusb-1.0-0-dev, libhidapi-dev and pkg-config packages installed

mkdir build && cd build
qmake ..
make install

Alternatively build as static module (best for portability)

mkdir build && cd build
qmake CONFIG+=qtusb-static ..
make install

MSVC
You need the Windows SDKs to compile libusb
These are available from the Visual Studio Installer
The following script builds and deploys QtUsb into your Qt installation

build_msvc.bat 2017|2019 x64|x86 module|static QT_PATH
ie: build_msvc.bat 2017 x64 static C:\Qt\5.14.1\msvc2017_64

Qt Creator
The module can also be built normally within QT creator regardless of the platform.
All dependencies are built with qmake.

Option 1: Using the module (static or dynamic)
You'll need to add the module to your project file:

qt += usb

Include headers:

#include <QUsbDevice>
#include <QUsbEndpoint>

Option 2: Importing the code in your project
This will tie your app to a specific Qt version as it uses private headers
You need to include the pri file into your qmake file:

include(QtUsb/src/usb/files.pri)

Include headers:

#include "qusbdevice.h"
#include "qusbendpoint.h"

QCH files can be found with each release, they are also included in ubuntu packages.
You have to manually install them in Qt Creator on Windows.
Online documentation can be found here

Ubuntu PPA Windows binaries are in the releases section.