Hello @SC9,
Yes, you should be able to update your project from TouchGFX 4.16.0 to 4.24.0. Please create a backup of your project before updating it to the latest version of TouchGFX.
If you don't want to migrate to TouchGFX 4.24.0, there is a custom container available for QR Code that you can access from here. To be honest, I haven't tested it with TouchGFX 4.16.0, but, there shouldn't be anything special about it that causes trouble.
In order to update your project to TouchGFX 4.24.0, first you need to open your TouchGFX project with 4.24.0, then generate code. Finally, you need to open your STM32CubeMX (.ioc) project and generate code from there as well (probably, you will be prompted to install X-CUBE-TOUCHGFX 4.24.0). And now, you should have your project ready.
I hope this helps you. Don't hesitate to ask more questions!