I don't use many paid 3rd party addons, but here's a few I found invaluable to my personal workflow:

Photographer (probably THE single most important camera tool I use every time I create a scene. Wouldn't render a scene without it)

Drop-It (simple but useful little addon for instantly dropping objects to either the grid, ground plane, or other objects in the scene. This is free.)

Camera-Plus (another great camera tool for making quick and easy changes to the camera position or simple camera animations)

HDRI Maker (outstanding for HDR environments with Eevee, has some handy features for shadow catching)

Animation Layers (wouldn't animate without this one. Extremely useful for mocap or BVH editing)

Sorry, can't link to any of the pay ones from here but they're all on Blender Market I think.

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