Free Texture Packer might be a bit more popular than Unity 2D. We know about 1 link to it since March 2021 and only 1 link to Unity 2D. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Unity: https://unity.com/solutions/2d Uses C# scripts. For more graphically intensive games. Source: over 1 year ago
Maybe something Free Texture Packer? It can target Unreal engine but I'm not sure what exact does that do. Personally I just pick the generic JSON option and parse the results to whatever format I currently need. Source: almost 2 years ago
Godot Engine - Feature-packed 2D and 3D open source game engine.
TexturePacker - Texture Packer is hands down the best sprite sheet generation tool on the market.
MonoGame - MonoGame is an open source implementation of the Microsoft XNA 4 Framework.
Sprite Monkey - Small and fast but still full-featured sprite sheet editor.
Creature - Creature 2D Skeletal and Mesh Animation Tool
ShoeBox - Free unlimited photo storage, so you can rediscover your photos anywhere. Available for iPhone, iPad, Android, Mac and PC.