by Nodes and noodles in Materials, Shaders, Textures

Will the nodes work in Eevee?

Yes, they will! The entire system is highly optimized so will not only work well for Eevee renders, but can even play in real time at 30-60 fps depending on scene complexity and hardware.

Why does Blender freeze for a few seconds when I use these nodes?

This will only happen with Eevee and is normal!
These nodes have extensive networks within them and so Eevee will take some time to compile shaders. Exactly how long it will take will depend on the hardware in use.