The orbs are created using Shader Graph and VFX Graph in Unity.
A YouTuber Gabriel Aguiar has released a new fantastic tutorial where the author explains how to create a procedural electric orb with Unity Shader Graph and how to use it with VFX Graph. According to Gabriel, the technique used in this tutorial is pretty quick, can be used with 3D objects, and doesn't require any drawing skills, only Unity.
Gabriel Aguiar Prod. is a channel that mostly focuses on creating Visual Effects for games. The creator has released various tutorials on using VFX and Unity Shader Graphs to create fantastic effects. You can check out some of the tutorials below or by visiting the Gabriel Aguiar Prod. YouTube channel.