Here are a few free plugins that offer glow effects, although they might not be an exact replica of Deep Glow:
Mimics how real light behaves in the physical world. deep glow after effects plugin free 2021
specifically for creating 3D spheres and planetary glow effects. Manual Glow Stack Here are a few free plugins that offer
: Set a low radius and high threshold to define the core brightness. deep glow after effects plugin free 2021
: The trial is free to download but will render a red 'X' watermark until a license is purchased. How to register plugins - aescripts.com
You can achieve a similar effect using only native After Effects tools by stacking multiple instances of the default effect: