I have just released an Aliens style motion tracker asset for use with Godot 4.x. It is ideal for topdown/overhead 2D games but could easily be adapted for a 3D game. The motion tracker asset is a shader and script that can be applied to either a ColorRect or TextureRect and will blend with their contents. The look of the tracker is customisable through the shader's parameters and with alternative code that is explained in comments within the shader and script.
It is distributed under the MIT Licence so can be freely used in your games as long as credit is given.
Click the link to try a simple test scene in browser and then download the project file.
https://steampunkdemon.itch.io/motion-tracker