In the video I show how to add a mesh to a sculpt directly in sculpt mode, with a mirror option for different axis. After adding the mesh I set the 3d cursor to the point that has been clicked to add the mesh, so that you can directly move, scale or rotate it in edit mode – even with the mirror modifier still enabled.

I also added the missing voxel remesher properties to the Remesh panel and use it after joining the objects to remesh and union the sculpted mesh.

The free addon can be downloaded here:
https://github.com/jayanam/fast-sculpt

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