Hello everyone, I’d like to share my attempt at merging all the things I’ve read about this material.
I think the result is pretty good!
Result:
This is the blueprint. I’ve put as many comments as possible to make it more comprehensible to everyone:
https://blueprintue.com/blueprint/2y3v8406/
For the less experienced: remember to set these properties:
NOTE: There is only 1 custom function that is needed to create a gradient to mask the borders. It’s called “Symmetric_Gradient”. Here it is:
You may notice I’ve tried to implement the vertex color override for the flowmap, but I’ve dropped this material it due to other work…
If you guys want to improve from this, I’ll be happy if you shared it with me! I’m still a noob! 
Cheers