Flared is a real-time lens flare generator add-on that works directly in the viewport of Blender, using Eevee engine. Download free at GFX-HUB.
You can have a direct preview of the final result without the need to use the compositor. It’s not screen space-based, so it works also when light sources move out of the screen. It takes advantage of procedural materials and it’s resolution-independent. It’s easy to use and customize and can help you to add cinematic looks to your 3D scenes or give more drama to your real video footage. Flared it’s not a physical simulation of the light path through the lens, it’s a powerful artistic instrument.