All Rule of thirds

Blender Development Fund
Asset Library
Blender Development Fund
Asset Library
SceneAssist — Composition Coach for Blender (Camera, Lighting, Balance)
$9.99

Skava in Addons

Camera Guides
$9

AllanSPK in Addons

Snapline - Rulers & Guides for Blender
$5

benedetto battipede in Addons

Camera Director Pro
$6.49

Steven Seidler (Blendscapes3D) in Addons