Hello Alexey,
Certainly, workflow is reduction of raw mesh to 200 million, then generate UVs and texture in Metashape with images as source. Further reduction to 50 million to export to Zbrush, import to Zbrush and project a subdivided plane to match the position of the mesh. Export the plane to Metashape, and build texture with the 200 million as the source.
In Substance Designer I can set the 'relative ray distance' to 1.0, 'relative to the bounding box' (not so clear an explanation), which is a wide enough range to capture all the geometry, both highest and lowest surfaces.
The reason I would like to use Metashape instead is higher resolution baking and I don't have to export/import huge meshes.
On that note a height baker would be fabulous which I know is often requested too. I know of one person who uses another software solely because it has a height baker, yet they have better results overall with Metashape.