I've a bit of ECS experience in Unity, and I found ECS in Murder much easier. The devs have done an awesome job. I
made a small arcade game project with Murder
https://nopetrides.itch.io/bombs-away that is available to play
In Murder, the editor lets you set up your sprite with hit boxes and entity components similar to working with Unity prefabs, but you can just drag those into the game world "scene" and they are already entities ready to go. Any systems will include the entities that it filters for without any additional steps. All you need to do is write the scripts for the components and systems, then add the component onto an entity into the world and add the system to the list of systems running in the world. Not to mention doing all that dynamically with support for more complex implementations.
TLDR; ECS in Murder is just regular C# with some different context. Learning ECS and using it in Unity was like a whole other world even for an experienced Unity programmer.