Actually this is just to tell you that there is a free alternative to TexturePacker, it's free-tex-packer. You may have already found that piece of software in any other site, but then when you check the repo you realize that's not maintained, so you may panic. Let's be realistic, it's only a texture packer, it doesn't need many changes over time, so I wouldn't worry about it, and just give it a try.
I tested it and works. There is no excuse to not use free-tex-packer if you want to stick to open source projects. But if you come from the JavasScript community you may be very worried that the project is abandoned, that's not true, the project just matured enough to be useful as it is.
Even if you are fine using proprietary software for this, keep in mind that TexturePacker sends data about the device you are using, plus it requires a license to export to phaser.js.